WILSON'S 


QUARTER  CENTURY 


IN 


PHOTOGRAPHY. 


A  COLLECTION  OF  HINTS  ON  PRACTICAL  PHOTOGRAPHY 


WHICH    FORM 


A  COMPLETE  TEXT-BOOK  OF  THE  ART. 


BY 

EDWAED  L.  WILSON, 

i  i  7 

HDITOK  OF  "THE  PHILADELPHIA  PHOTOGRAPHER,"  AUTHOR  OF  "WILSON'S  PHOTOGRAPHICS,"  "PHOTOGRAPHIC 

MOSAICS,"  TTC. 


OP 

(iTnriTEHSITY 


The  camera  is  mightier  than  the  pen  or  the  pencil. 

NEW  YOEK: 
PUBLISHED   BY  EDWARD  L.   WILSON, 

No.  853  BROADWAY. 

1887. 


Entered,  according  to  Act  of  Congress,  in  the  year  1887,  by 
EDWARD  L.  WILSON, 

4^  ^^^7 

In  the  office  of  the  Librarian  of  Congress/at  Washington,  D.  C. 


> 


TO 

THE  VETERAN  PHOTOGRAPHERS 

WHO  FOR  A 

QUARTER  OF  A  CENTURY  HAVE  FOCUSSED  THE  CAMERA, 
FIVE  HUNDRED  OF  WHOM  I  WOULD  LIKE  TO  MENTION  BY  NAME, 

AND  TO  THE 

YOUNGER  ONES  WHO,  WITH  THEM,  ARE  HONESTLY  LABORING  TO  UPHOLD  THE  MOST 
BEAUTIFUL   ART-SCIENCE   EVER   DISCOVERED, 


fllns    fjook    is    inscribed, 


BY  THE  AUTHOR. 


PREFACE. 


A  QUARTER  of  a  century  ago  I  abandoned  the  vocation  of  merchant,  to 
which  I  had  been  trained  against  my  will,  and  entered  the  establishment 
of  Mr.  F.  Gutekunst,  photographer,  Philadelphia,  as  ah  employe. 

With  a  sort  of  a  there-must-be-hypo-in-the-wash-water  look  in  their 
faces,  many  friends  advised  against  such  a  course,  averring  that  Photography 
was  aa  circus  kind  of  a  business,  destined  to  a  short  life,  and  unfit  for  a 
gentleman  to  engage  in." 

But  frequent  visits  to  the  studios  of  some  photographic  friends  had 
caused  me  to  be  fascinated  with  the  art.  I  believed  in  it,  became  an 
optimist  concerning  it,  engaged  in  it,  and  in  about  a  year  announced  myself 
as  editor  in  chief  of  a  magazine  whose  purpose  it  should  be  to  elevate 
Photography  and  to  do  what  it  could  to  help  those  who  became  devoted  to  it 
with  me. 

This  work  has  gone  on  ever  since.  The  Philadelphia  Photographer,  like 
a  great  journalistic  funnel,  has  received  and  let  through  without  interruption 
the  generous  offerings  of  our  co-workers  from  all  parts  of  the  world. 

Much  of  what  they  gave  has  become  covered  up  and  forgotten.  For 
the  past  two  years  I  have  been  engaged  in  a  process  of  recovery,  selection, 
filtration,  and  condensation,  the  result  of  which  goes  out  now  in  the  book 
accompanying  this. 

It  is  issued  just  now  as  an  anniversary  offering.  If  I  live  to  do  the 
same  work  again,  I  shall  be  an  old  man,  and  Photography  will  doubtless 
be  able  to  present  us  with  portraits  of  the  people  of  other  worlds  provided 
it  keeps  sailing  on  at  its  present  speed. 

(V) 


VI  PREFACE. 

I  have  tried  to  make  Quarter  Century  in  Photography  useful  alike  to 
learner  and  earner — a  book  fully  up  to  the  times,  and  helpful  for  all  time. 

Where  our  art  has  been  the  weakest,  I  have  endeavored  to  be  the 
strongest.  Where  I  have  been  weak,  I  have  called  in  the  words  of  wiser 
workers.  This  plan  proved  so  acceptable  in  Wilson's  Photographies,  that 
I  have  ventured  to  follow  it  in  this  work.  I  send  it  forth  with  the 
hope  that  it  may  help  maintain  the  high  position  our  beloved  art  has 
attained,  and  hold  up  the  hands  of  the  noble  men  and  women  who  are 
devoted  to  it,  for  at  least  another  Quarter  Century. 

EDWARD  L.  WILSON. 

YORK,  June  1,  1887. 


AUTHORITIES  QUOTED  IN  THIS  VOLUME. 


ABNEY,  W.  DE  B. 
ADAMS,  CHARLOTTE. 
ADAMS,  W.  I.  L. 
ALBERT,  EUGENE. 
ANDRA,  M. 
ANDRE,  E. 

ANTHONY  &  CO.,  E.  &  H.  T. 
ARCHIV  PHOTOG. 
ASHMAN,  W.  M. 

BACHRACH,  D.,  JR. 
BAKER,  W.  J. 
BALAGNY,  G. 
BALM  AN,  JAMES. 
BARATTI,  OTTAVIO. 
BARDWELL,  JEX. 
BEACH,  F.  C. 
BEECHY,  ST.  VINCENT. 
BELL,  WILLIAM. 
BEND  ANN,  DANIEL. 
BENECKE,  R. 
BETTINI,  A. 
BIGELOW,  L.  G. 
BLAKE,  JOHN  M. 
BLANCHARD,  VALENTINE. 
BODE,  W. 
BOIVIN,  ERNEST. 
BOTHAMLEY,  C.  H. 
BREBNER,  HUGH. 
BRIT.  JOURNAL  OF  PHOTOG. 
BROOKS,  WILLIAM  ROBERT. 
BROWN,  HENRY  W. 
BROWN,  M.  P. 
BROWNE,  JOHN  C. 
BURNET,  JOHN. 
BURRIT,  JOSEPH  C. 
BURTON,  W.  K. 
BUTTERFIELD,  J.  C. 

CAMERA,  THE. 
CARBUTT,  J. 
CASSAN,  M. 
CHANDLER,  W.  D. 
CHEVREUL. 

CHENEVIERE,  ROBERT. 
CHUTE,  R.  J. 
CLARK,  FORESTER. 
CODDTNGTON,  G  .W. 


COOPER,  DAVID. 

GORCOIX,  CAPT. 

CORMANY,  M.  L. 

GREEN,  ARTHUR. 

COURTIER,  E. 

GRISWOLD,  M.  M. 

CRAMER,  G. 

CROOKE,  WILLIAM. 

HALL,  B.  F. 

CROUGHTON,  G.  HANMER. 

HARRISON,  W.  H. 

HART,  WILLIAM. 

DALLMEYER,  J.  H. 

HANSON,  W. 

DANIEL,  H.  A.  H. 

HASSELBERG,  HERR. 

DAY  ANNE,  A. 

HEARN,  CHARLES  W 

DEAN,  C.  W. 

HENRY,  MONS. 

DENSMORE,  JAY. 
DESSODEUX,  M. 

HEPWORTH,  T.  C. 
HERMAGIS,  J.  FLEURY. 

"DEXTER." 

HICKOX,  R.  A. 

DOANE,  E. 

HILL,  C.  WALTON. 

DOUGLASS,  RANALD. 

HOLYOAKE,  W.  R. 

DUNCAN,  DAVID. 

HORGAN,  S.  H. 

DUNMORE,  EDWARD. 

HOUGH,  E.  K. 

D  WIGHT,  M.  L. 

HULL,  CHARLES  WAGER. 

EASTMAN,  GEORGE. 

HUNT,  0.  W. 

EDER,  J.  M. 
EDMONDSON,  G.  W. 
EDWARDS,  B.  J. 

INGE  &  ADDENBROOK. 
INGLIS,  JAMES. 

EHINGER,  MRS.  CLYDE. 

IVES,  F.  E. 

ELLERBECK,  J.  H.  F. 
EL  LINGER,  J.  0. 
EMERSON,  P.  H. 
ENGLAND,  WILLIAM. 

JACOBSEN,  E. 
JANE  WAY,  DR.  JOHN  H. 
JASTRZEMBSKY,  M. 

ENNIS,  GEORGE. 
ESKIL,  J.  J. 
EVANS,  CHARLES 

JOHNSON,  J.  R. 
JOHNSTON,  H.  M. 
JOLY,  M.  E. 

FENNEMORE,  GEORGE  H. 

KENT,  J,  H. 

FISCH,  A. 

KIBBE,  W.  H. 

FOSS,  E.  J. 

KILBURN,  B.  W. 

FOXLEE,  G.  W. 

KIMBALL,  H.  A. 

FRENCH,  C.  M. 

KING,  JOSEPH  W. 

FRENCH,  WILFRED  A. 

KLAUSER,  KARL. 

FREY,  EMIL. 

KLEARY,  C. 

FRIEDRICH,  FRANZ. 

KLEIN,  M. 

FRY,  SAMUEL. 

KNIEBEL,  FRANZ. 

KNOWLTON,  CHARLES. 

GARRETT,  ELWOOD. 

KOEHLER,  S.  R. 

GARRETT,  C.  ALFRED. 

KONARZEWSKI. 

GAUSE,  J.  EZRA. 

KRAUSS,  CHARLES. 

GELDMACHER,  F.  W. 

KRUSE,  HERR. 

GIHON,  JOHN  L. 

KURTZ,  HENRY. 

GLINES,  W.  B. 

KURTZ,  WILLIAM. 

(vii) 

Vlll 


AUTHORITIES    QUOTED    IN    THIS    VOLUME. 


LANDY,  JAMES. 
LATCHMORE,  THOMAS. 
LAWS,  M. 
LEAKE,  J.  C. ' 
LEA,  M.  CAREY. 
LEAS,  GEORGE  W. 
LIBBY,  E.  P. 
LIEBERT,  M. 
LIESEGANG,  E. 
LINN,  U.  M. 
LISTER,  HENRY. 
LOESCHER  &  PETSCH. 
LOESCHER,  P. 
LONDE,  ALBERT. 
LONG,  E. 

LONGFELLOW,  H.  W. 
LUCKHARDT,  F. 

MACBETH,  NORMAN. 
MAC  NICHOL,  WILLIAM. 
MAGEE,  JAMES  F. 
MALLMAN,  H 
MANVILLE,  W.  A. 
MARSHALL,  A. 
MASON,  J.  S. 
MASON,  S.  RUFUS. 
McCORMICK,  C.  A. 
McINTIRE,  II.  M. 
"MEISKNBACH." 
MONCKHOVEN,  D.  VON 
MONROE,  G.  H. 
MOORE  BROTHERS. 
MORAN,  JOHN. 
MORRISON,  R. 
MORTON,  HENRY. 
MOTES,  C.  W. 
MOTTU,  P.  A. 
MULLEN,  JAMES. 

NADAR*,  PAUL. 
NEWTON,  H.  J. 
NICOL,  JOHN. 
NISBET,  HUME. 
NOSS,  H. 

OBERNETTER,  J.  B. 
0' MADDEN,  CHEVALIER. 
ORMSBY,  E.  D. 
OSBORNE,  J.  W. 

PARIS  MONITEUR. 
PARSONS,  S.  H. 
PASSAVANT,  S.  C. 
PEARSALL,  G.  F.  E. 
PICKERING,  W.  H. 
PILE,  W.  H. 
PIPER,  HENRY. 
PIZZIGHELLI  &  HUBL. 


PLATT,  S.  L. 
PHOTO  -ARCHIV. 
POITEVIN,  M. 
POWELL,  GEORGE  MAY. 
POWELL,  M. 
PRAY,  THOMAS,  JR. 
PRETSCH,  MAX.     . 
PRUMM,  H. 
PUBLIC  OPINION. 

RAWSON,  D.  W.  S. 
REUTLINGER,  C. 
REYNOLDS,  SIR  JOSHUA. 
RICH  ARSON,  C.  F. 
ROBBIXS,  FRANK. 
ROBINSON,  H.  P. 
ROBINSON,  S.  M. 
ROCHER,  H. 
ROCHE,  T.  C. 
ROOD,  F.  M. 
ROOT,  SAMUEL. 
ROSE,  P.  H. 
ROTHE,  HERR. 
RUSKIN,  JOHN. 

SALOMON,  ADAM. 
SAUNDERS,  IRVING. 
SCHELL,  GEORGE  W. 
SCHNITZER,  C.  C. 
SCHOLTEN,  JOHN  A. 
SCHOONMAKER,  H. 
SCHUMANN,  V. 
SCOFIELD,  C.  H. 
SCOLIK,  C 
SCOTFORD,  J.  H. 
SEAVEY,  L.  W. 
SEDGWICK,  H.  M. 
SELLSTEDT,  L.  G. 
SEYBOLD,  H.  K. 
SHAKESPEARE 
SHEPARD,  THOMAS  P. 
SHERMAN,  W.  H. 
SIMON,  M.  C. 
SIMPSON,  G.  WHARTON. 
SMITHELLS,  EDWARD. 
SMITH,  D.  EDSON. 
SMITH,  J.  EDWARD. 
SMITH,  W.  G. 
SMITH,  XANTHUS. 
SNELL,  WILLIAM. 
SOUTHWORTH,  ALBERT  S. 
SPENCER,  F.  M. 

SPENCER,  F.  W. 
SPERING,  GEORGE. 
SPERRY,  GEOI:<;I:. 
SPICE  R,  ALEX. 
SPILLER,  JOHN. 


SPITALER,  HERR. 
SQUIBB,  EDWARD  L. 
STEBBINS,  E. 
STERNBERG,  L. 
STEVENS,  C.  N. 
STILLMAN,  W.  J. 
STOOD ARD,  S.  R. 
STOLZE,  E. 
STONE,  LONDON. 
STUART,  JOHN. 
STURENBERG,  C. 
SUTTON,  THOMAS. 

TAYLOR,  REV.  A.  A   E. 
TAYLOR,  WILLIAM  CURTIS. 
TISSANDIER,  G. 
TOWLER,  JOHN. 
TOWNSEND,  DAVID. 
THIEBAULT,  M. 
THOMAS,  FRANK. 
TRASK,  A.  K.  P. 
TURNBULL,  A.  E. 


VAN  WEIKE,  ROLAND. 
VERCOE,  H.  T. 
VERRES,  HERR, 
VEVERS,  C.  C. 
VIDAL,  LEON. 
VOGEL,  II.  W. 

WALDACK,  CHARLES. 
WALKER,  W.  H. 
WALLACE,  GEORGE  W. 
WALL,  A.  H. 
WARNERKE,  L. 
WEBSTER,  I   B. 
WEISS,  R.  G. 
WELLINGTON,  J.  B.  B. 
WELLS,  T.  M. 

WHITE,  GEORGE  WILLIAM. 
WHITNEY,  L.  M. 
WIGHT,  M. 
WILDE,  W.  F. 
WILKINSON,  W.  T. 
WILLIS,  W. 
WILSON,  F.  II. 
WILSON,  W. 
WISE,  G.  W. 
WOODBURY,  W.  B. 
WOODMAN,  CLARENCE. 
WRATTEN  &  \VAIX\VUIG1IT. 
WRIGHT,  WILLIAM  R. 

ZAY,  F.  II. 
ZENTMAYER,  JOSEPH 


CONTENTS 


CHAPTER  I. 

PAGE 

THE  HISTORY  OF  PHOTOGRAPHY         .  .....      17\ 

CHAPTER  II. 

THE  THEORY  OF  PHOTOGRAPHY 


CHAPTER   III. 
LIGHT 

CHAPTER  IV. 
THE  CAMERA 


CHAPTER  V. 

ABOUT  LENSES     .  .  33 

CHAPTER  VI. 
THE  DIAPHRAGM  OR  STOP  .....  65 

CHAPTER  VII. 

GLASS-HOUSE  CONSTRUCTION       ....  .  .75 

CHAPTER  VIII. 

UNDER  THE  SKYLIGHT        ...  .  .  105 

(ix) 


X  CONTENTS. 

CHAPTER  IX. 

PAGE 

THE  APPLICATION  OP  ART  PRINCIPLES       .  .   '141 

CHAPTER  X. 
OUTDOOR  OPERATIONS 182 

CHAPTER  XI. 
EXPOSURE  OR  THE  QUESTION  OF  TIME 220 

CHAPTER   XII. 
CONCERNING  CHEMICALS 239 

CHAPTER   XIII. 
DARK-ROOM  CONTRIVANCES         .........     251 

CHAPTER   XIV. 

NEGATIVE-MAKING — "  WET  "  ....     287 

CHAPTER  XV. 
NEGATIVE-MAKING — "DRY" .311 

CHAPTER   XVI. 
NEGATIVE-MAKING — "PAPER  AND  FILM  " 418 

CHAPTER  XVII. 

RETOUCHING  AND  DOCTORING  THE  NEGATIVE    .        .        .        .        .        .  *  435 

CHAPTER   XVIII. 

PRINTING  ON  ALBUMENIZED  PAPER    .  .  .         .     442 

CHAPTER  XIX. 

PRINTING — DRAWBACKS  AND  DEFECTS  ;  CAUSES  AND  REMEDIES        .        .    458 


CONTENTS.  xi 

CHAPTER  XX. 

PAGE 

PRINTING-ROOM  PARTICULARS     .  463 


CHAPTER  XXI. 

PECULIAR  PRINTING  PROCESSES  ....  .  .  474 

CHAPTER  XXII. 

COLOR-SENSITIVE  PHOTOGRAPHY — ISOCHROMATIC — ORTHOCHROMATIC       .    504 

CHAPTER   XXIII. 
PHOTO-ENGRAVING 509 

CHAPTER  XXIV. 
LANTERN  SLIDES  AND  TRANSPARENCIES    .  515 


LIST  OF  ILLUSTRATIONS. 


Prof.  Charles'  Silhouette     . 
Refraction  of  Light      . 

The  Eye 

Formation  of  an  Image 
Zentmayer's  Lens  Illustrations  34,  3' 
43,  45,  46,  48,  49,  50,  51,  53,  54,  55, 
Lens  Grinding      .... 
Finishing  a  Lens 
Mounting  a  Lens 
Focal  Length  of  a  Lens 
Angle  of  View  of  a  Lens      . 
Optical  Centre  of  a  Lens 
The  Diaphragm  or  Stop 
The  Guillotine  Stop      . 
The  Flare  Stop     .... 
Lea's  Illuminated  Stop 
The  Inclined  Stop 
Perforated  Diaphragms 
Zentmayer's  Revolving  Stop 
Measuring  the  Light   . 
American  Model  Glass-house 
A  Modified  Model  Glass-house     . 
J.  H.  Kent's  Glass-house     . 
James  Landy's  Glass-house 
Lighting  the  Model     . 
A  Canadian  Glass-house 
High  and  Low  Glass-house 
Position  of  the  Model  . 
Direction  of  the  Light 
P.  A.  Mottu's  Glass-house   . 
A  Southern  Exposure  .        . 
A  Roof  Studio      .... 
F.  Luckhardt's  Glass-house 
"  Curiosity  "  Skylight 
A  Texas  Glass-house    .         .        . 
Sash  Bar  Contrivance  . 
Ground  Plan  of  H   Rocher's  Studio 
N.  P.  A.  Model  Glass-house 
Steven's  Photographic  Car  . 
Glass-house  Roof  Construction     . 
Plan  of  a  Photographer's  Tent    . 
Outdoor  Posing-room  . 
P.  H.  Rose's  Reception-room 
P.  H.  Rose's  Studio      . 


PAGE 

.  19 

.  28 

.  31 

.  32 

5,  37,  38,  40,  42, 

56,^7,58,59,60,  63 

.      ,35,  37 

.  39 

.  39 

.  43 

.  44 

.  53 

.  65 


.  70 

.  71 

.  72 

.  74 
75,  76 

.  77 

.  78 

.  79 

.  80 

.  81 


83,  84,  85 
.     85 


.     87 

.  87,  88 
.  89 

.  89,  90 
.  91 

.       92,  93 

93,  94,  96,  97 

.     95 

.     96 

.     98 

.  98,  100 
.  100 
.  102 
.  103 
.  104 


PAGE 

Loescher  &  Petsch's  Curtain  Plan        .        .         .        .105 

Kent's  Hand-screen     ....  .         .  106 

Densmore's  Side  Screen       ....  .  107 

King's  Top  and  Side  Screens       ...  .  108 

Hall's  Circular  Head  Screen  .  .  .108 

Manville's  Reflectors 108 

Kibbe's  Camera  Vignetting  Device  ....  10!) 

Mason's  Screen  Fixture 100 

Combination  Screen  and  Sight  Point  ....  110 

Moss's  Adjustable  Screen Ill 

Cramer's  Black  and  White  Screen  .  .  .  .112 

Griswold's  Concave  Reflector 113 

Kurtz's  Adjustable  Screens 114 

FOBS' s  Sub- studio 115 

Coddington's  System  of  Reflectors  ....  110 
Mote's  Circular  Background  .  ...  120 

Salomon's  Concave  Background  .  .  .121 

Kurtz's  Cone  Background 122 

Baratti's  Revolving  Background  .  .  123 

Platt's  Rotary  Rest .  127 

Smith' s  Copy  ing  Board  128 

Benecke's  Copying  Board 128 

Spencer's  Copying  Board 130,  131 

Fennemore's  Copying  Camera  ....  130,  131 

Chute's  Focussing  Apparatus 132 

Spencer's  Curtain  Stand  .  .  .  .  .  .133 

Edmonson's  Camera  Vignette 135 

Brown's  Camera  Multiplier  ....  136,  137 

Coddington's  Baby  Shutter 137 

Thomas's  Lens  Hood 138 

Prism  for  Reversal  of  the  Image  ....  139 
Rawson's  Multiplying  Reflector  .  .  .139,  140 
Portrait  of  Thomas  Le  Clear,  by  W.  Donovan  .  .  143 
"  The  Ruins  of  Gertasse,"  by  L.  de  Forest  .  .  144 
"The  Temple  of  Paestum,"  by  J  F  Cropsey  .  .  145 
"  The  Pursuit  of  Knowledge  under  Difficulties,^'  by 

Wordsworth  Thompson 146 

"The  Testy  Old  Squire's  Complaint,"  by  Geo.  H. 

Story 148 

"  A  Sketch,"  by  F.  S  Church 152 

"  First  Come,  First  Served,"  by  Frost  Johnson  .  156 
"Sunny  Afternoon,  Algiers,"  by  S  Coleman  .  .  157 
"Girl  Spinning."  by  Wm.'Magrath  .  .  .  .158 
"We  all  do  Fade  as  a  Leaf,"  by  Jennie  Brownscombe  159 

(Niii) 


XIV 


LIST    OF    ILLUSTRATIONS 


PAGE 

"The  Sabot  Maker,"  by  E  M.  Ward  .  .  .162 
"Heligoland,"  by  Hermann  Eschke  ....  1G7 

"Autumn,"  by  F.  Cranberry 171 

"Return  from  the  Ridotto,"  by  A.  H.  Baldwin  .  172 
" The  Courier,"  by  C.  F.  Blauvelt  .  .  .  .173 
"Off  Cape  Hatteras,"  by  Edward  Moran  .  .  .174 
"  Amsterdam,"  by  Eliza  Greatorex  .  .  .  .175 

Nine  Portraits  of  Chevreul 180 

<:  A  Landscape,"  by  Winslow  Homer  .  .  .  .183 
"Bouquet  River  in  Winter,"  by  Gi-o.  B.  Wood,  Jr.  .  184 
"LakeLenian,"byJ.  H.  Casilear  .  .  .  .185 

"Evening,"  by  R.  C.  Minor 186 

"A  Scene  in  New  Hampshire."  by  J.  H  Casilear  .  187 
"Mount  Equinox,"  by  J.  B.  Bristol  .  .  .  .188 
"Mountain  Lake,"  by  Albert  Bierstadt  .  .  .188 
"  The  Gull  Rock,"  by  W.  T.  Richards  .  .  .188 
"The  Harbor  Bar,"  Mount  Deseret,  by  D.  M.  Arm- 
strong. ...  189 

"Off  the   North  Head,"   Grand   Menan,  by  A.  T. 

Bricher 190 

"  From  a  North  River  Pier,"  by  Arthur  Quart! ey     .  190 

Fowler's  "Sky  "  Diaphragm 192 

Illustrations  in  Perspective  .  .  .  193,  196,  197 
"An  August  Morning,"  by  R.  Swain  GifTord  .  .194 
"Harbor  Islands,  Lake  George,"  by  H.  W.  Robbing,  195 

"On  the  Desert,"  by  Frank  Waller    .        .        .        .195 

"  Cedars  of  New  England,"  by  R.  Swain  Gifford  .  196 
Illustration  of  Height  and  Distance  .  .  .  .198 

"A  Group  of  Sheep,"  by  T.  Robinson        .        .        .200 

"The  Arrival  of  the  Stage,"  by  J.  Wells  Champney   201 

"New  England  School,"  by  A.  F.  Bellows 

'  A  Merry  Tale,"  by  H.  P.  Robiusou 

"The  Harvesters  at  Rest,"  by  Wyatt  Eaton 

"Answering  the  Horn,"  by  Winslow  Homer    . 

"Noonday  in  the  Pasture,"  by  A.  D.  Shattuck 

"The  Washing-place— Brittany,"  by  E.  M.  Ward 

"Penfield's  View,"  by  Edward  Gay    . 

An  Ideal  Landscape 

Multiplying  Contrivance     .... 

Illustrating  Perspective       ... 

Exposing  Shutters 

Diaphragms 

Developing  Tents         .... 

Vidal's  View  Meter      .... 

Stebbing's  View  Meter 

Beechey's  Exposing  Shutter 

"  The  Indispensable  " 

Speed  Measurer  ..... 


202 
203 
205 
205 
206 
207 
.  207 
.  208 
.  209 
.  211 

.  212,  213 
.  214 
.  215,  216 
.  217 
.  218 
.  218 
.  219 
.  231 


Dial  Instrument  for  Measuring  the  Exposure     .         .  232 

Warnerke's  Sensitometer 234 

Vogel's  Sensitometer 236 

Nicol's  Sensitometer 237 

Hcrmagi's  Sensitometer 238 

Densmorc's  Water  Still 246 

Leake's  Dark-room  Sink 251 

Model  Dark-room 252 

Lea's  Method  of  Washing  Glass  .        .        .  .253 


Vever's  Dark-room  Ventilator 

Taylor's  Dark-room  Light  .... 

Root's  Bath  Cooler 

Platt's  Heating  Lamp 

Long's  Bath  Warmer  and  Cooler 
Wells'8  Waste-pipe  Model    .... 
Scotford's  Solution  Cooler   .... 
Smith's  Apparatus  for  Distilling  Water 
Osborne's  Water- vessel        .... 
Spicer's  Plaited  Filter .        .        .        . 

Garrett's  Filterer 

Woodman's  Filterer 

Kurtz's  Filterer 

Platts's  Filterer 

Schoonmaker's  Developing-bottle 

Lea's  Plate-holder 

Brooks's  Filter-stand 

Courtier's  Rocking  Device  .... 
Stebbing's  Rocking  Device  .... 
German  Rocking  Device  .... 

German  Plate  Tongs 

Duncan's  Developer  Cup     .... 

The  Pipette 

Stebbing's  Pipette 

Hepworth's  Four-poster      .... 

Gause's  Siphon     .... 

Chandler's  Siphon 

Stebbing's  Bath  Emptier     .        .        . 

Stebbiug's  Siphon 

Vidal's  Apparatus  for  Decanting  Collodion 

Green's  Dry-plate  Drying  Rack  . 

The  Actino  Hydrometer      .... 

Vogel's  Silver  Tester   .  . 

Pile's  Silver  Tester      .  ... 

Webster's  Silver  Saver         .... 

Benecke's  Silver  Saver         .... 

Kilburn's  Silver  Pourer       . 

Vidal's  Filtering  Tray          . 

Kruse's  Negative  Numberer 

Vidal's  Portable  Laboratory 

Root's  Plate-cleaning  Device 

Bettini'sWashing  Machine 

Varnish  Pourers 

Spencer's  Negative  Cleaner 

Negative  Defect 

Foxlee's  Horizontal  Bath    .... 

Platt's  Emulsion  Plate  Apparatus 

Vogel's  Emulsion  Preparer 

Vogel's  Lamp 

Eder's  "Spray"  Apparatus 

Davanne's  Emulsion  Bottle 

Stebbing's  Emulsion  Apparatus  . 

Vogel's  Emulsion  Stirring  Apparatus 

Wratten  &  Wainwright's  Stirring  Washer 

Schuman's  Emulsion  Washer 

Turubull's  Emulsion  Washer 

Vogel's  Emulsion  Filter       .         .        .        . 


.  295 
.  260 
.  260 
.  261 
.  261 
.  262 
.  263 
.  263 
.  264 
.  264 
.  265 
.  265 
.  266 
.  267 
.  267 
.  268 
.  268 


270 

270 
271 
271 
272 
273 
274 
275 
275 
279 


.  281 
.  282 
.  283 
.  283 
.  284 
.  284 
.  285 
.  286 
.  287 
.  300 
301,  302 
.  304 
.  305 
.  306 
.  315 
.  316 
.  310 
.  319 
.  320 
.  321 
.  323 
.  335 


336 
337 


LIST    OF    ILLUSTRATIONS. 


Vogel's  Plate  Dryer 
Stebbing's  Plate  Dryer 
Henry's  Plate  Washer 
Gorcoix's  Plate  Washer 
Weiss'  s  Developing  Tray 
Scofield's  Developing  Tray 
Obernetter's  Emulsion  Washer 
Emulsion  "  Tear-drops  " 
Defects  of  Emulsion  Plates 
An  Emulsion  Film 
Eastman's  Film  Carrier 
Eastman's  Roll  Holder 
Balagny's  Stirator        ... 
The  Engraving  Diamond 
Marshall's  Varnish  Pourer 
Gihon's  Negative  Etcher 
Kimball's  Printing-room  Plans  . 
Wise's  Paper-  box 
Kilburn's  Paper-saver         . 
Hull's  Silvering  Table          .        . 
Tnrnbull's  Paper  Dryer 


PAGE 

338 
339 
364 
365 
365 
366 
376 
395 
.405 

420,  423 
424 

425,  426 

.  433 

440 

440 

441 

443,  444 

447 

448 

.449 

450 


Streaked  Paper 

Platt's  Heating  Lamp 

Leas'  Washing  Tank 

The  Squeegee 

Gihon's  Paper  Sensitizer 

Parson's  Fuming  Box 

Clark's  Printing-frame  for  Aqua  Tints 
Moore  Bro's  Printing-frame  for  Handkerchiefs 
Printing-frame  for  Waymouth's  Vignettes 

Robinson's  Sky-Mask 

Ormsby's  Glace  Press 

Frey's  Mounting-brush 

Dexter's  Enlarging  Helps 

Eastman's  Easel  for  Enlargements 

Beach's  Enlarging  Apparatus      .         .        .    485, 

Platinum  Developing  Tray 

Liebert's  Porcelain  Printing- frame     . 
Ives's  Isochromatic  Portraits      .... 
Hogan's  Photo-engraving  Diagrams   . 
Browne's  Camera  Box  for  Glass  Positives  . 


PAGE 
.  452 
.  454 
.  457 
.  463 
-  463 
.  464 
.  465 
.  466 
.  467 


.  472 
.  473 

483,  485 
.  484 

486,  487 
.  48<> 
.  499 
.  505 
.  510 
.  515 


OP  THE 

VEHSIT7 


WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


CHAPTEE   I. 

THE   HISTORY   OF   PHOTOGRAPHY. 

1.  PHOTOGRAPHY,  wise  men  tell  us,  is  the  art  of  drawing  by  light. 

If  this  is  true,  then  Adam,  when  he  came  to  the  "knowledge  of  good  and 
evil,"  became  also  the  first  discoverer  of  photography.  He  saw  his  full  length 
shadow  pursuing  him,  and  tried  to  hide  from  it.  He  was  glad  enough,  doubt- 
less, that  it  diminished  as  the  day  went  on,  and  that  it  was  not  fixed.  Since 
his  time,  however,  men  have  arisen  who,  prompted  more  by  the  love  of  the 
beautiful  than  by  the  dread  of  shadows,  have  endeavored  to  render  permanent 
the  wonderful  traceries  of  the  sun. 

Their  achievements,  which  enable  us  every  one  to  make  home  more  beauti- 
ful, and  which  have  made  all  of  our  lives  happier,  entitle  them  to  a  word  of 

1.  What  a  pity  that  stern  and  splendid  old  realist,  Oliver  Cromwell,  did  not  live  to 
have  his  portrait  taken — "wart  and  all!"  The  note  of  photography  rings  thoroughly  in 
accord  with  present  art  tendencies.  They  would  have  clean  naturalness,  faithful  real- 
ism, clear  detail;  these  she  gives.  There  is  greater  fondness  for  landscape  than  ever 
before ;  this  is,  above  all,  the  province  and  most  favorable  field  of  photography.  The 
life  of  the  time,  studies  and  stories  of  the  people;  she  can  render  these.  Late-born,  she 
is  in  sympathy  with  the  age.  She  is  in  the  very  forefront  of  the  march  of  modern 
feeling. 

The  future  holds  great  things  for  her.  She  has  battles  to  win,  wars  against  foes  within 
and  without— against  the  fever  of  facility,  against  cheapness  and  carelessness  and  igno- 
rance, that  have  brought  down  on  her  artistic  dislike  and  popular  light  esteem.  But 
beyond  a  doubt  she  will  feurmount  these  troubles  as  she  grows,  and  gain  the  place  she 
deserves ;  and  it  will  be  by  the  aid  and  effort  of  the  men  who  gallantly  and  rightly  seek 
to  exalt  their  calling,  to  make  it  pure  and  of  good  report,  and  to  hold  as  high  and  as 
honorable  as  any  the  name  of  Artist-Photographer. — F.  H.  WILSON. 

The  discovery  of  photography  ranks  amongst  the  most  wonderful  applications  of 
modern  science ;  we  owe  it  almost  solely  to  the  genius  of  Niepce  and  Daguerre.  If  we 
2  (17) 


18          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

mention,  even  in  a  work  which  can  only  briefly  make  record  of  about  twenty- 
five  years  of  the  growth  of  their  art. 

2.  Permit  me  to  begin. 

First  came  the  philosopher,  lasso  in  hand,  who  captured  the  shadow,  and 
held  it  long  enough  to  give  his  friends  a  sight. 

This  was  Jean  Baptiste  Porta,  the  inventor  of  the  Camera  Obscura.  He 
lived  in  the  latter  half  of  the  sixteenth  century. 

Through  a  tiny  hole  in  a  shutter  the  rays  of  light  entered  into  a  dark-room 
and  drew  upon  a  white  screen  the  image  of  objects  outside,  reversed. 

Although  the  same  process  had  been  going  on  all  over  the  world  since 
Adam,  Porta  seems  to  have  been  the  first  one  who  discovered  it.  Enraptured, 
he  placed  a  convex  lens  in  the  aperture  in  his  shutter  and  then,  catching  the 
image  upon  a  mirror,  reversed  it. 

But  his  lasso  was  not  powerful  enough  to  hold  what  he  had  caught.  Many 
a  mind  was  set  to  work  to  help. 

An  alchemist  came  next  with  mysterious  subtlety,  and  took  hold.  In  his 
search  for  the  Philosopher's  Stone  he  discovered  chloride  of 'silver.  Spreading 
some  of  it  upon  a  flat  surface,  he  noticed  that  any  image  projected  upon  it  by 

could  know  the  obstacles  which  these  great  minds  had  to  overcome  before  solving  a 
problem  which  had  long  been  looked  upon  as  Utopian,  we  could  see  with  what  perse- 
verance the  inventor  must  arm  himself  to  attain  his  ends.  Nothing  is  more  instructive 
than  the  impartial  history  of  great  discoveries ;  it  shows  us  how  slow  is  the  march  of 
progress,  and  how  many  beacons  must  shine  along  the  course  of  centuries  to  guide  the 
inventor  into  regions  of  the  unknown.  First  appears  a  man  who  sows  the  germ,  others 
follow  and  cultivate  it,  up  to  the  time  when  some  genius  fertilizes  and  renders  it  fruitful. 

— G.  TlSSANDIER. 

2.  The  germ  of  photography  is  the  dark-room  (or  camera  obscura),  discovered  in  the 
second  half  of  the  sixteenth  century,  by  J.  B.  Porta,  a  clever  Italian  philosopher. 

The  process  which  the  illustrious  Neapolitan  employed  was  most  simple.  He  made  an 
aperture,  hardly  large  enough  to  admit  the  little  finger,  in  the  shutter  of  a  window  so 
perfectly  closed  as  entirely  to  exclude  light.  The  rays  of  light  penetrating  the  circular 
hole  into  the  dark-room  were  projected  upon  a  white  screen,  on  which  they  depicted  the 
reversed  image  of  exterior  objects.  The  simple  observation  of  Nature  might  have  led  at 
once  to  this  discovery.  The  foliage  of  trees  does  not  entirely  intercept  the  sun's  light ; 
it  often  allows  rays  of  light  to  pass  through  the  spaces  which  exist  between  the  leaves, 
and  the  images  of  the  ruler  of  the  day  appear  as  luminous  disks  in  the  midst  of  the  well- 
defined  shadows  on  the  ground.  It  is  easy  to  reproduce  this  phenomenon  by  passing 
the  light  of  a  candle  across  a  small  orifice,  and  projecting  it  on  to  a  screen,  on  which  a 
reversed  image  of  the  flame  will  be  seen. — G.  TISSANDIER. 


THE    HISTORY    OF    PHOTOGRAPHY. 


19 


FIG.  1. 


means  of  his  lens  was  imprinted  with  all  the  gradations  of  Nature  translated 
into  blacks  and  grays. 

But  Fabricus,  for  he  it  was,  let  the  rope  slip  through  his  fingers,  because  he 
was  looking  for  something  more  substantial  than  shadows. 

In  1760  Triphaiue  de  la  Roche,  a  native  of  Normandy,  was  told  by  the 
genii  that  a  certain  subtle  ingredient  spread  upon  canvas  would  secure  images 
from  Nature  cast  thereon  an:]  fix  them.  He  was  either  too  frivolous,  or  too 
secretive  to  reveal  more,  and  again  the  lasso  failed. 

In  1777,  Scheele,  the  famous  chemist  of  Sweden,  discovered  that  chloride  of 
silver  was  much  more  sensitive  to  the  rays  of  blue  and  violet  in  light  than  it 
was  to  those  of  red  and  green. 

3.  In  1780,  Prof.  Charles,  in  a  course  of  lectures,  by  means  of  a  strong 
solar  ray  projected  a  shadow  of  the  head  of  one  of  his  pupils  upon  a  sheet  of 
white  paper  which  had  been  soaked 
in  a  solution  of  chloride  of  silver,  and 
secured  a  silhouette  in  white  on  a  black 
ground — but  it  fled  on  exposure  to  the 
light. 

Wedgewood  and  Sir  Humphrey 
Davy  made  similar  experiments,  and 
in  1802  published  a  remarkable  treat- 
ise on  the  reproduction  of  objects  by 
light. 

James  Watt,    the   inventor  of  the 
steam-engine,   also  interested   himself 
in  this  research ;  but  for  none  of  the 
distinguished  scientists  would  the  captured  imagery  remain  when  facing  the 
sun,  its  creator. 

3.  Porta  lost  no  time  in  recommending  the  use  of  the  dark-room  to  all  painters 
desirous  of  obtaining  exact  and  minute  delineation ;  and,  shortly  afterward,  Canaletto 
profited  by  his  advice,  and  employed  the  invention  for  taking  his  admirable  views  of 
Venice. 

What  would  the  Neapolitan  philosopher  and  the  Venetian  painter  have  said  had  they 
been  told  that  this  image  of  the  dark-room  would  one  day  draw  itself,  not  merely  fugi- 
tively,  but  that  it  would  print  itself  on  a  glass  moistened  with  chemical  agents  ?  that  it 
would  transform  itself  into  a  durable  picture,  only  to  be  compared  for  exactness  to  the 
reflection  of  a  mirror?  This  wonder  was,  indeed,  to  be  accomplished  unknown  to  Porta; 
but  his  work  was  not  in  itself  sufficient  to  conduct  science  to  such  a  result;  numerous 
laborers  had  also  to  add  their  stone  to  the  edifice.— G, 


20  WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

It  was  reserved  for  two  Frenchmen  to  so  deftly  throw  and  strain  the  snare, 
that  the  fugitive  was  at  last  captured.  Their  names  are  familiar — Daguerre 
and  Niepce.  Examples  of  their  individual  work  are  not  uncommon,  and 
everybody  has  seen  daguerrotypes  made  by  their  followers. 

Mr.  Fox  Talbot,  an  Englishman,  came  almost  simultaneously  with  Daguerre 
and  Niepce,  with  his  paper  negatives. 

4.  Not  much  progress  was  made,  however,  until,  in  1851,  Mr.  Scott  Archer 
made  public  the  collodion  process  upon  glass.  That  became  the  master  of 
them  all,  and  has  been  most  largely  in  use.  Its  modifications  have  been 
almost  endless.  Many  of  them  will  be  detailed  in  the  pages  which  follow, 
together  with  a  record  of  some  of  the  successes  which  have  rewarded  indus- 
trious experiment  to  overcome  the  drawbacks  of  the  collodion  process  upon 
glass. 

As  a  result  of  such  experiment,  collodion,  the  silver  bath,  and  even  glass, 
are  falling  more  and  more  into  disuse. 

The  names  of  the  good  people  who  have  brought  about  these  marvellous 
changes  are,  as  nearly  as  I  can  collate  them,  enrolled  herein,  and  much  of  what 
they  have  said  is  recorded  in  this  work. 

Photography  is  !  It  has  no  real  rival.  And  when  I  come  to  tell  of  some 
five-and-twenty  years  of  its  life,  at  the  very  beginning  I  see  I  am  going  to  be 
crowded  for  space,  and  therefore  must  not  devote  much  to  history,  or  to  theory, 
or  even  to  praise. 

To  the  work  then  ! 

4.  "  Photography  is  still  in  its  infancy."  This  is  a  phrase  which  has  been  so  often 
reiterated  within  the  last  thirty  years  that  it  seems  about  time  to  drop  it.  If  photography 
were  still  in  its  swaddling  clothes  after  so  long  a  period,  we  might  well  despair  of  its 
ever  attaining  to  manhood.  That  this  is  not  the  case,  however,  will  become  apparent  at 
once  if  we  consider  for  a  moment  the  consequences  which  would  attend  its  sudden 
demise,  if  that  were  possible.  It  would  be  felt  as  a  shock  throughout  the  whole  civilized 
world ;  it  would  create  a  void  which  thousands  of  minds  would  at  once  endeavor  to  fill. 
This  is  not  the  result  which  follows  the  death  of  an  infant.  Its  fond  parents  may  shed 
tears  of  anguish,  and  the  friends  of  the  parents  may  mourn  their  sorrow ;  but  the  world 
remains  unmoved,  and  continues  its  occupations  as  if  nothing  had  happened. 

Nevertheless,  it  goes  without  saying  that  photography  has  not  yet  reached  the  end  of 
its  development,  and  that  a  long  period  of  advance  is  still  before  it.  How  would  it  do 
then  if  we  called  it  a  youth  instead  of  an  infant?  And  a  promising  youth,  too,  who 
has  already  given  proof  of  his  great  powers,  has  scored  not  a  few  victories  in  the  race  of 
life,  and  is  still  hard  at  work  with  all  his  faculties  unimpaired  upon  the  problems,  the 
solution  of  which  he  has  set  himself  as  his  special  task.— S.  R.  KOEHLER. 


CHAPTER   II. 

THE  THEORY  OF  PHOTOGRAPHY* 

5.  ALL  photographic  images  may  be  divided  into  two  classes,  the  apparent 
and  the  latent. 

Chloride  of  silver  is  usually  employed  in  producing  apparent  images,  as  in 
sun-printing,  and  was  the  material  used  by  the  early  experimenters. 

Iodide  of  silver  is  mostly  employed  for  latent  images. 

With  chloride  of  silver  the  changes  caused  by  the  action  of  light  are  visible 
to  the  eye. 

When  iodide  of  silver  is  used  as  the  base  of  operations,  the  changes,  though 
just  as  real,  are  invisible  until  certain  other  chemical  agents  are  brought  into 
contact  with  it,  and  develop  them. 

For  our  purpose  light  is  divided  into  chemical  or  actinic  rays — such  as 
affect  the  silver  salts — and  non-actinic  rays,  which  create  no  change  in  the 
silver  salts. 

Recent  experiments,  however,  have  resulted  in  securing  active  service  from 
nearly  every  color  of  the  prism,  under  proper  conditions. 

Red  and  yellow  being  non-actinic,  by  admitting  into  the  developing-room 
only  such  light  as  comes  through  glass,  or  other  media  of  these  colors,  all 
harm  from  light  in  the  wrong  place  is  avoided. 

So  much  for  light  on  the  theory  before  us. 

5.  Photography,  like  many  other  things,  may  be  viewed  from  many  standpoints.  It 
may  be  viewed  artistically,  theoretically,  practically,  or  historically.  Each  and  all  of 
these  ways  would,  doubtless,  be  of  interest ;  but  let  us  look  at  the  theory  of  photography. 
Chemistry  has  taken  unto  itself  optics,  and  from  these  two  has  sprung  another  science — 
photography — combining  the  characteristics  of  its  progenitors.  We  have  two  ways  to 
treat  of  the  theory  of  photography,  then — chemical  and  physical.  Let  us  take  the 
former.  But  while  chemistry  may  boast,  while  physics  may  boast,  of  having  endowed 
photography  with  many  things,  it  cannot  be  denied  that  she  has  taken  to  herself  many 
things  that  neither  chemistry  nor  physics  can  boast.  Springing  thus  from  an  earth  of 
exact  mathematical  science,  photography  has  grown  upward  until  she  spreads  her 
branches  in  the  heavens  of  art. — HENRY  M.  M'INTIRE,  M.  E. 

(21) 


22          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

6.  Now  as  to  the  formation  of  the  photographic  image  by  means  of  the 
action  of  light  upon  silver  salts.  Whether  bromide,  chloride,  or  iodide  is 
used,  the  action  is  similar.  Iodide  will  be  used  for  the  present  illustration. 

,  To  a  solution  of  nitrate  of  silver  we  add  a  small  quantity  of  the  soluble 
iodide  of  some  metal,  say  ammonium.  Iodide  of  silver  is  thus  formed. 

We  use  plain  collodion  as  the  vehicle  for  the  operation.  It  has  no  influence 
upon  the  chemical  reaction. 

Certain  salts  which  contain  bromine  and  iodine  are  dissolved  in  plain  collo- 
dion, and  such  iodized  collodion  is  flowed  over  a  glass  plate,  and  allowed  to 
set.  The  film  is  then  immersed  in  a  solution  of  nitrate  of  silver.  Whilst  still 
moist,  the  film  is  taken  out  of  the  bath  and  exposed  to  the  action  of  light.  The 
rays  of  light  are  directed  by  a  lens  and  form  an  image. 

The  formation  of  a  subiodide  of  silver  is  caused  by  the  change. 

If  no  body  which  will  absorb  iodine  be  present  this  change  will  not  take 
place,  for  if  we  thoroughly  wash  a  plate  on  taking  it  out  of  the  bath,  and 
attempt  to  develop  it,  after  exposure  to  light  no  alteration  in  its  aspect  will  be 
manifest.  It  is  therefore  evident  that  in  wet  photography  the  nitrate  of  silver 
plays  an  important  part. 

In  dry-plate  photography  the  action  of  light  is  precisely  the  same,  but  the 
free  nitrate  of  silver  solution  is  replaced  in  this  case  by  some  body  which  will 
combine  with  iodine. 

6.  It  is  a  firm  fact  of  chemistry  that  if  two  solutions  are  poured  together,  and  by  any 
change  a  salt  can  be  formed  that  will  be  insoluble  in  the  resulting  liquid,  that  salt  is 
bound  to  be  formed,  and,  being  formed,  to  be  precipitated. 

Thus,  the  bromine  by  leaving  its  ammonium,  and  the  silver  by  leaving  its  nitric  acid, 
find  that  they  can  unite  together,  and  form  an  insoluble  salt.  And  now  the  ammonium 
being  left,  the  nitric  acid  being  left  with  nothing  else  to  do,  unite  with  each  other,  and 
form  nitrate  of  ammonium,  which,  being  soluble,  must  remain  in  solution. 

If,  in  place  of  the  bromide  of  ammonium,  we  should  substitute  iodide  of  ammonium, 
we  should  obtain  similar  results,  a  precipitate  of  iodide  of  silver.  (AgN03  +  NH4I  = 
Agl  -f-  NH4NO3,  nitrate  of  silver  and  iodide  of  ammonium  make  iodide  of  silver  and 
nitrate  of  ammonium.)  And  also,  if  in  place  of  the  iodide  or  bromide  of  ammonium,  we 
should  put  some  other  iodide  or  bromide,  we  should  obtain  like  results,  precipitates  of 
iodide  or  bromide  of  silver,  as  the  case  might  be. 

Now  let  us  take  some  salted  collodion,  and  flow  a  glass  plate  with  it ;  we  have  then  the 
glass  covered  with  a  thin  film  of  collodion,  which  acts  as  a  ground  or  vehicle,  and  contains 
a  bromide  and  an  iodide.  This  plate  is  now  placed  in  the  silver  bath.  What  takes  place 
there  is  easily  said.  The  bromide  in  the  collodion  causes  bromide  of  silver  to  be  pre- 
cipitated upon  the  plate,  and  the  iodide  in  like  manner  iodide  of  silver,  and  we  have, 


THE    THEOKY    OF    PHOTOGRAPHY.  23 

7.  The  change  to  the  state  of  subiodide  being  invisible  or  latent,  we  must 
find  some  agent  which  will  make  the  chemical  action  apparent.  Pyrogallic 
acid  is  a  chemical  well  known  for  its  affinity  for  oxygen/  as  are  the  ferrous  or 
proto-salts  of  iron,  the  latter  tending  to  form  the  ferric  or  per-salts  that  are 
combined  with  more  oxygen.  I  will  take  the  example  of  the  latter  when 
applied  to  the  latent  image.  Its  use  is  based  on  the  assumption  that  the  sub- 
iodide  of  silver  has  an  affinity  for  metallic  silver,  and,  consequently,  causes  the 
silver  from  the  free  nitrate  solution  to  be  deposited  by  the  developer  upon 
those  parts  acted  upon  by  light.  For  greater  regularity  and  less  rapidity  of 
action  acetic  acid  is  added  to  the  developer. 

If  sufficiently  slow,  the  subiodide  will  attract  all  the  particles  of  metallic 
silver  as  they  are  formed,  and  thus  build  up  a  metallic  image.  In  practice  the 
acid  added  is  just  sufficient  to  cause  this  gradual  reduction  of  the  silver.  Heat 
increasing  the  rapidity  of  the  chemical  action,  it  follows  that  in  decidedly  hot 
weather  a  larger  quantity  of  acetic  acid  should  be  used  than  in  cold. 

The  stronger  the  iron  solution  the  greater  chemical  power  it  will  have,  and 
the  more  rapidly  it  will  decompose  the  silver  solution.  As  a  consequence,  with 

when  the  plate  is  taken  from  the  bath,  a  thin  but  uniform  film  of  bromide  and  iodide  of 
silver,  and  adhering  to  this  some  of  the  bath — a  solution  of  nitrate  of  silver. 

The  plate  is  now  placed  in  the  dark-slide,  and  exposed.  What  effect  does  the  exposure 
have  on  the  plate  ?  Here  we  meet  face  to  face  the  question,  What  is  the  chemical  action 
of  light  ?  Let  us  look  at  a  few  experiments.  If  we  take  some  chloride  of  silver,  some 
bromide  of  silver,  and  some  iodide  of  silver,  and  expose  these  to  the  action  of  the  sun- 
light, we  will  see  that  they  all  darken,  that  the  chloride  becomes  a  violet  color,  the 
bromide  yellowish-gray,  and  the  iodide  greenish.  It  may  also  be  noticed  that  from  the 
chloride  free  chlorine  escapes,  and  from  the  bromide  and  the  iodide  bromine  and  iodine, 
as  the  case  may  be. — HENRY  M.  M'!NTIEE,  M.  E. 

7.  On  account  of  the  reducing  power  of  light,  a  picture  could  be  made  upon  the  pre- 
pared platfe  in  the  camera ;  this  would  require  hours  of  exposure.  But  in  place  of  this, 
another  property  is  made  use  of;  that  is,  the  attraction  existing  between  the  silver  film 
acted  upon  by  the  light,  and  metallic  silver  in  a  finely  divided  state. 

It  has  been  found  that  the  parts  of  the  exposed  plate  that  have  been  acted  upon  by 
the  light  have  a  great  attraction  for  small  particles  of  metallic  silver.  It  is  only  required 
then  that  the  plate  be  covered  with  silver  in  a  finely  divided  state.  How  can  this  be 
done? 

This  can  be,  and  is  done,  by  the  developer.  There  is  upon  the  surface  of  the  negative 
a  solution  of  nitrate  of  silver,  which  it  brought  from  the  bath.  This  serves  as  the  source 
of  the  metallic  silver.  But  this  is  not  the  only  good  office  that  this  solution  performs. 
If,  when  the  plate  is  submitted  to  the  action  of  the  light,  and  the  chlorine,  bromine,  or 
iodine  is  given  off,  there  be  something  to  catch  and  retain  the  chlorine,  bromine,  or 


24          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

a  strong  solution,  all  parts  of  the  picture  acted  upon  by  light  will  immediately 
become  nuclei  for  the  deposition  of  silver,  and  the  deposit  will  be  of  more  even 
density  than  if  a  weaker  solution  had  been  employed ;  for  with  the  latter  those 
parts  most  acted  upon  by  the  light — i.  e.,  which  had  been  most  thoroughly 
converted  into  subiodide — having  the  most  attractive  force,  would  draw  the 
deposit  of  silver  to  them,  and  the  image  would  be  much  more  intense  at  those 
parts  than  where  the  light  had  less  strongly  acted. 

Either  pyrogallic  acid  or  protosulphate  of  iron  may  be  employed  with  nitrate 
of  silver,  to  cause  an  increase  of  density  by  thickening  the  deposit  of  the 
metallic  silver.  This  is  called  intensifying.  The  reactions  are  analogous  to 
those  of  development,  excepting  that  the  metallic  silver  is  the  attractive  matter 
instead  of  the  subiodide.  Both  these  have  the  property  of  assisting  the  decom- 
position of  the  solution  of  the  silver  salt,  as  before  stated.  The  silver  must  be 
reduced  gradually  to  the  metallic  state,  when  it  will  be  deposited  on  those  parts 
on  which  silver  has  already  been  reduced  by  the  action  of  the  developer,  in  the 
ratio  of  their  densities. 

iodine,  the  sensitiveness  will  be  found  to  be  increased,  and  this  the  bath  solution  does. 
Being  a  solution  of  nitrate  of  silver,  as  soon  as  the  chlorine,  bromine,  or  iodine  strikes  it, 
it  seizes  at  once  upon  that  chlorine,  bromine,  or  iodine,  and  makes  them  its  own  in  the 
shape  of  chloride,  bromide,  or  iodide  of  silver. 

We  have  then  upon  the  exposed  plate  a  solution  of  nitrate  of  silver ;  from  this  the 
metallic  silver  must  be  obtained.  How  can  this  be  done  ? 

By  a  "reducing  agent; "  something  that  will  take  away  the  nitric  acid  from  the  silver, 
and  leave  the  silver  in  its  free  state.  Hence  the  developer  contains  a  reducing  agent, 
either  pyrogallic  acid  or  protosulphate  of  iron.  The  action  of  either  of  these  is  the  same. 
—HENRY  M.  M'!NTIRE,  M.  E. 

The  theory  which  I  propose  may  be  summed  up  in  the  following  propositions : 

a.  Pure  iodide  of  silver  is  always  sensitive* to  light. 

b.  When  isolated,  it  is  never  decomposed  by  light,  but  undergoes  a  merely  physical  or 
molecular  change.  • 

c.  But  when  exposed  in  the  presence  of  free  nitrate  of  silver,  it  undergoes  with  time  a 
distinct  and  abundant  reduction. 

d.  This  reduction  is  to  a  sub-iodide,  and  not,  as  supposed  by  some,  to  metallic  silver. 
From  these  propositions  there  result  the  following  important  corollaries : 

a.  The  image  on  pure  iodide  of  silver,  isolated,  is  single. 

b.  That  on  iodide  of  silver  moistened  with  solution  of  nitrate  of  silver,  may  be,  arid 
probably  generally  is,  double.    That  is,  it  consists  of  a  physical  image  impressed  upon 
particles  of  iodide,  and  they  may  also  be  a  reduced  image  due  to  the  nitrate  of  silver. 

c.  Where  an  organic  film  is  present,  containing  the  iodide,  and  the  whole  is  moistened 
with  nitrate  of  silver,  the  image  may  be  triple — it  may  consist  of  the  two  former  with  the 
addition  of  a  third,  due  to  the  organic  matter,  as  exemplified  in  iny  experiments  of 


THE    THEORY    OF    PHOTOGRAPHY.  25 

8.  After  the  development  of  the  latent  image  the  iodide  and  bromide  of 
silver  are  left  unaltered,  and  probably  the  subiodides  and  bromides. 

Looking  at  the  reverse  side  of  the  plate  (that  which  does  not  bear  the  film), 
the  green  color  of  the  iodide  and  bromide  of  silver  will  be  apparent. 

Were  this  unaltered  iodide  and  bromide  of  silver  left  in  the  film,  a  print 
taken  from  it  on  paper  in  the  ordinary  manner  would  be  found  to  be  nearly'  a 
blank,  the  iodide  and  bromide  possessing  almost  as  much  power  of  preventing 
the  passage  of  light  as  the  reduced  silver  itself.  Certain  chemical  solutions, 
however,  are  found  to  be  capable  of  dissolving  the  iodide  and  bromide,  leaving 
the  metallic  silver  unchanged. 

These  chemical  solutions  are  termed  "fixing  solutions"  and  the  operation  of 
dissolving  out  the  iodide  and  bromide  of  silver  is  termed  "fixing  the  image." 
These  terms  apply  equally  to  those  agents  and  operations  in  printing  which 
render  the  image  permanent.  Here,  however,  chloride  of  silver  is  acted  upon. 

removal  of  the  iodide  by  solvents,  and  production  of  a  picture,  independently  of  the 
iodide. 

It  also  results  from  the  foregoing  that  the  physical  theory  is  preeminently  the  true 
one,  because  those  holding  that  opinion  have  never  denied  that  the  silver  haloids  were, 
under  favorable  circumstances,  reducible  by  light,  and  our  view  that  a  developable  image 
may  be  produced,  independently  of  any  reduction  or  decomposition,  is  one  that  has  been 
placed  beyond  controversy. — M.  CAREY  LEA. 

8.  And  now  the  plate  is  to  be  fixed-  For  this  purpose,  we  have  choice  of  two  solutions 
— hyposulphite  of  soda  and  cyanide  of  potassium.  As  the  theory  of  both  is  ultimately 
the  same,  let  us  look  only  at  the  action  of  the  cyanide  of  potassium. 

Nitrate  of  silver  and  cyanide  of  potassium  form  cyanide  of  silver  and  nitrate  of  potas- 
sium. If  we  take  this  precipitate,  and  treat  it  with  some  more  cyanide  of  potassium,  we 
will  find  that  it  will  dissolve,  the  double  cyanide  of  silver  and  potassium  being  formed — 
AgCy  +  KCy  =  (Ag  -f-  K)Cy2.  Cyanide  of  silver  and  cyanide  of  potassium  form  the 
double  cyanide  of  silver  and  potassium.  If  we  should  now  experiment  upon  the  action 
of  potassium  cyanide  upon  metallic  silver,  we  should  find  that  it  will  have  no  effect  upon 
it,  except  in  the  presence  of  the  oxygen  of  the  air. 

We  can  now  see  at  a  glance  what  an  efficient  agent  this  will  be  for  fixing ;  how  when 
it  is  poured  upon  the  plate  it  will  attack  the  silver  unacted  upon  by  light,  changing  the 
bromine  and  iodide  into  cyanide ;  going  still  farther,  how  it  will  dissolve  this  cyanide 
when  it  is  formed.  But  all  this  time  it  will  have  no  effect  on  that  substance  produced 
by  the  combined  action  of  light  and  the  developer,  metallic  silver.  But  the  fact  that  in 
presence  of  air  it  will  attack  the  metal,  shows  the  necessity  of  having  the  fixing  solution 
to  cover  the  entire  plate,  and  also  of  pouring  it  off  quickly  and  washing  with  water 
immediately.  The  action  of  hyposulphite  of  soda  is  similar  to  the  cyanide. — HENRY  M. 

M'lNTIRE,  M.  E. 


26          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Dismissing  the  chlorides  of  the  alkalies  and  iodide  of  potassium  (owing  to  their 
imperfections  as  fixing  agents),  the  first  solvent  of  iodide,  bromide,  or  chloride 
of  silver  that  is  to  be  noticed  is  hyposulphite  of  soda. 

The  chemical  reaction  of  this  salt  upon  the  bromide  is  similar  to  that  upon 
the  iodide.  The  double  salt  is  soluble  in  a  solution  of  hyposulphite  of  soda ; 
consequently  the  darkest  shadows  of  the  image  will  be  rendered  transparent 
through  the  removal  of  the  iodide,  by  the  application  of  the  latter  in  excess. 

The  only  other  fixing  agent  that  is  in  general  use  is  cyanide  of  potassium. 
It  is  very  poisonous. 


CHAPTEE   III. 

LIGHT. 

9.  WE  have  already  learned  that  light  is  the  chief  producing  agent  in  pho 
tography.     If  light  could  be  called  an  inventor,  the  photographic  image  might 
well  be  regarded  as  the  acme  of  its  genius.     The  astounding  changes  on  which 
our  art  depends  exceed  in  interest  everything  else  under  the  sun.     Every 
element  of  light  seems  to  be  required  in  their  production. 

These  elements  or  qualities  of  light  are  numerous.  They  are  intensity ; 
"  regular"  reflexion ;  "  irregular"  reflexion  ;  refraction  ;  dispersion,  and  ab- 
sorption. 

The  sources  of  light  employed  in  photography  are  both  natural  and  artificial. 
Of  course,  the  sun  is  the  chief. 

9.  In  the  constant  trials  that  are  made  of  new  sources  of  light  for  photographic  uses, 
enough  attention  seems  scarcely  to  have  been  paid  to  the  nature  of  the  light,  as  well  as 
to  its  brilliancy.  No  fact  is  more  familiar  than  that  all  highly  actinic  artificial  light  is 
either  blue  or  bluish,  and  it  seems  certain  that  if  any  given  light  were  to  be  tinged  with 
blue  its  actinic  power  would  be  thereby  materially  increased. 

The  light  of  burning  magnesium  acts  more  powerfully  than  the  lime  light,  which  is 
far  more  intense.  Evidently  this  is  owing  to  its  blue  tinge.  It  would,  therefore,  be  a 
very  interesting  experiment  to  tinge  the  lime  light  blue,  and  observe  whether  its  actinic 
power  would  not  be  greatly  heightened  thereby.  This  effect  should  not  be  produced  by 
interposing  blue  glass,  which  cannot  increase  the  blue  rays,  but  would  probably  be  pro- 
duced by  soaking  the  lime  cylinder  in  a  strong  solution  of  copper  salt — probably  a 
saturated  solution  of  chloride  of  copper  would  be  the  most  effectual.  The  experiment 
could  be  easily  tried  by  those  who  are  in  the  habit  of  using  the  lime  light,  and  might 
give  exceedingly  interesting  results. — M.  CAREY  LEA. 

Dr.  Monckhoven's  night  light  consists  of  the  oxyhydrogen  light,  with  pillars  of  pure 
carbonate  of  magnesia  instead  of  lime  cylinders.  The  result  is  a  light  with  the  chemical 
intensity  of  the  ordinary  magnesium  light,  without  its  unsteadiness  and  irregularity,  a»nd 
at  a  less  cost ;  or,  in  other  words,  it  is  a  Drummond  light  with  a  much  higher  actinic 
power  than  that  of  incandescent  lime.  The  light  is  intense,  concentrated,  actinic,  steady, 
and  continuous,  supplying  all  the  conditions  requisite  for  photographic  enlarging 
operations. — DR.  H.  VOGEL. 

The  electric  light  will  be  given  attention  further  on. 

(27) 


28 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


10.  Intensity,  in  degree,  is  governed  by  the  source  and  by  the  medium 
through  which  the  light  must  pass  in  order  to  reach  any  given  point. 

Reflexion  is  "regular"  when  the  beam  of  white  light  falls  upon  a  surface 
and  is  transmitted  from  it  as  white  light. 

Reflexion  is  "  irregular "  when  it  falls  upon  bodies  which  take  up  certain 
portions  only  of  the  colored  rays  composing  white  light,  and  reflecting  those 
tints  alone,  absorb  the  rest,  and  the  objects  appear  to  us  colored. 

Refraction  is  the  change  of  direction  which  a  beam  of  light  acquires  in  pass- 
ing from  a  medium  of  one  density,  as  air,  to  another  of  different  density,  as 
water  or  glass. 

10.  The  first  thing,  then,  to  be  noted  of  light  is  that  it  travels,  when  left  to  itself,  in 
straight  lines ;  but  as  soon  as  it  enters  a  substance  of  a  different  density,  then  its  path  is 
changed  at  the  point  where  it  leaves  the  one  and  enters  the  other.  Having  once  entered 
the  new  medium,  it  continues  in  a  straight  line  in  its  new  course  until  it  meets  another 
medium,  and  one  of  different  density.  This  bending  of  the  ray  of  light  is  called  refraction, 
and  the  following  facts  have  been  noticed  in  regard  to  this  refraction.  The  ray  that  is 

,  passing  through  the  first  me- 

FIG.  2.  dium  is  called  the  incident  ray, 

27  and  tjiis  one,  after  it  is  bent,  the 

refracted  ray;  the  line  drawn  at 
the  point  where -the  ray  leaves 
one  medium  and  enters  the 
other,  perpendicular  to  the  sur- 
face of  the  media,  the  normal  ; 
the  angle  which  the  incident 
ray  makes  with  the  normal,  the 
angle  of  incidence;  and  the 
angle  which  the  refracted  ray 
makes  with  the  normal,  the 
angle  of  refraction.  That  is, 
referring  to  Fig.  2,  A  C  is  the 
incident  ray ;  C£,  the  refracted 
ray :  D  E,  drawn  perpendicular 

to  the  surface  of  the  media,  F  G,  the  normal ;  A  CD,  the  angle  which  A  C  makes  with 
this  normal,  the  angle  of  incidence;  and  B  C  E,  the  angle  which  B  C  makes  with  the 
normal,  the  angle  of  refraction. — HENRY  M.  M'!NTIRE,  M.  E. 

A  strong,  high  light  affects  the  chemical  substances  used  in  photography  much  more 
rapidly  and  powerfully,  comparatively  speaking,  than  a  mellow,  diffused,  or  half-light. 
Perhaps  the  point  will  be  better  understood  by  considering  the  following  mathematical 
formula :  Let  the  high-light  be  equal  to  one  hundred ;  then  black,  as  the  absence  of  all 
light,  theoretically  at  least,  will  be  equal  to  0;  half-light  will  be  equal  to  fifty ;  quarter, 
equal  to  twenty-five ;  and  so  on.  Now  let  ten  seconds  be  the  time  required  for  the  high- 


d 


~ 


&%=*&-_ 


G 


LIGHT.  29 

Iii  the  construction  of  lenses  advantage  is  taken  of  this  quality  of  light  by 
the  use  of  optical  glass  varying  in  density,  thus  securing  the  whitest  possible 
light,  or  achromatism. 

Dispersion  is  the  separation  of  a  beam  of  white  light  into  its  component 
rays  which  vary  from  each  other  in  color  and  in  refrangibility. 

The  prism  disperses  the  rays  of  light  and  creates  the  solar  spectrum.  The 
clouds  scatter  the  rays  of  the  sun  and  produce  the  glories  of  sunset  and 
sunrise. 

When  a  narrow  beam  of  light  is  admitted  into  a  darkened  room  it  will 
illumine  an  object  close  to  the  point  of  entry.  Remove  the  object  further  and 
further  away,  soon  it  ceases  to  be  visible.  This  is  because  of  the  absorption  of 
the  light.  Some  surfaces,  like  velvet,  coarse  papers,  and  fabrics  absorb  light. 

11.  Understanding  fairly  these  varied  qualities  of  light,  we  shall  see,  as  we 
go  on,  how  mysteriously  they  enter  into  the  practice  of  photography,  either  in 

light  to  produce  its  full  effect,  that  is  to  say,  so  to  change  the  chemical  substance  used  as 
to  render  it  completely  insoluble.  If  the  process  went  on  with  equal  rapidity  all  over 
the  plate,  the  chemical  substance  would  be  one-half  destroyed  in  the  half-lights  at  the 
end  of  the  same  ten  seconds ;  one-quarter  in  the  quarter-lights ;  and  so  on.  This,  how- 
ever, is  not  the  case  in  practice.  While  the  full  light  exerts  its  full  effect  in  ten  seconds, 
the  half-light,  being  more  feeble,  may  require  fifteen  seconds  to  exert  its  full  effect,  the 
quarter-light  twenty  seconds,  and  so  on.  If,  therefore,  the  quarter-light  is  to  be  shown 
at  its  full  force,  necessitating  an  exposure  of  twenty  seconds,  the  half-light,  which  ought 
to  stop  at  fifteen  seconds,  will  have  to  be  over-exposed  for  five  seconds;  during  which  five 
seconds  it  continues  to  work  on  the  chemical  substance  still  undecomposed,  and  the  result  is  a 
falsification  of  the  gradations,  a  heightening  of  the  contrasts  between  light  and  dark, 
and  a  tendency  to  destroy  those  middle  tones  which  give  unity  and  artistic  beauty  to  a 
picture.  To  recur  once  more  to  our  formula :  at  the  end  of  twenty  seconds,  the  propor- 
tion instead  of  being  1  =  100;  £  =  50;  £=25;  will  probably  be  something  like  this: 
1  =  100 ;  £  =  60  ^  \  =  25.  It  is  evident  from  this  that  the  harmony  must  be  destroyed. 
On  the  other  hand,  if  the  exposure  had  been  limited  to  ten  seconds,  the  result  would 
have  resembled  this  formula :  1  =  100 ;  \  =  40 ;  \  =  15 ;  that  is  to  say,  we  would  have 
seen  glaring  high-lights  in  a  surrounding  mass  of  dimness  and  darkness.  And  this  is 
actually  the  case  in  so-called  under-exposed  pictures. — S.  R.  KOEHLER. 
11.  Remember  these  points : 

a.  The  high-lights  act  more  rapidly,  they  take  hold  of  the  plate  more  suddenly  than 
lower  lights. 

b.  They,  therefore,  accomplish  their  full  results  in  comparatively  much  less  time  than 
lower  lights. 

c.  Photographic  action  decreases  in  the  inverse  ratio  to  the  length  of  exposure. 
From  all  this,  the  difficulty  of  the  following  problem,  with  the  ordinary  methods  of 

photography,  will  be  readily  understood :    Given,  a  bride  in  a  white  dress  to  be  photo- 


30          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

the  management  of  the  lens  and  diaphragm  or  in  the  selection  and  arrange- 
ment of  the  subject.  They  govern  the  whole  process,  and  are  sometimes  very 
exacting.  But  if  we  carefully  consider  them  and  conform  to  their  rules  they 
will  usually  be  good  to  us. 

What  follows  relative  to  lenses  will  give  further  light  on  this  subject. 

graphed  against  a  white  background.  In  this  case  the.  tints  of  the  flesh  will  be  the 
darkest  part  of  the  picture  (even  if  we  ignore  entirely  the  additional  difficulty  resulting 
from  the  red  and  yellow  rays  reflected  by  the  flesh).  By  the  time,  therefore,  when  the 
higher  lights  in  the  white  drapery  have  produced  their  full  effect,  the  face  and  arms  are 
still  so  underdeveloped,  that,  if  the  exposure  were  then  stopped,  these  parts  would 
appear  altogether  too  dark.  But  if,  on  the  contrary,  the  exposure  were  continued  until 
the  face,  etc.,  are  properly  developed,  the  delicate  shadows  in  the  white  drapery  and 
background  would  all  be  burned  away  by  overexposure,  and  the  result,  although 
.  different,  would  be  equally  disagreeable. — S.  B.  KOEHLER. 

The  effect  produced  by  a  given  light  in,  say,  ten  seconds,  is  not  duplicated  by  another 
exposure  of  ten  seconds ;  and  the  feebler  the  light  the  greater  the  difference  in  the  effect 
produced  during  each  subsequent  period  of  equal  duration.  For  example :  A  strong 
light  acting  on  a  plate  probably  produces  fifty  per  cent,  of  its  maximum  effect  in  the  first 
two  seconds,  twenty -five  per  cent,  more  in  the  three  seconds  following,  and  the  remain- 
ing twenty-five  per  cent,  in  the  five  seconds  left.  The  full  effect  having  then  been 
reached,  that  is  to  say,  the  decomposition  or  change  of  the  chemical  substance  having 
been  completed,  the  process  stops.  With  the  half-light  the  case  is  different :  Fifteen 
seconds  being  needed  for  the  production  of  its  legitimate  effect,  twenty-five  of  its  fifty 
per  cent,  are  perhaps  effected  within  the  first  three  seconds,  twelve  and  one-half  per 
cent,  more  in  the  following  five  seconds,  and  the  other  twelve  and  one-half  per  cent,  in 
the  remaining  seven  seconds.  But  here  the  process  does  not  stop,  and  while  the  quarter- 
lights  and  still  lower  lights  are  being  developed,  the  half-light  goes  on  increasing  in 
brightness,  as  previously  explained,  although  in  an  inverse  ratio  to  the  length  of  time, 
that  is  to  say,  with  constantly  decreasing  rapidity. — S.  K.  KOEHLER. 

Some  new  values  have  been  given  to  light  recently  as  applied  to  photographing  colors 
and  colored  objects,  whereby  true  color- value  is  obtained.  The  interesting  and  useful 
results  are  detailed  further  on. — EDWARD  L.  WILSON. 


CHAPTEE   IV. 


THE  CAMERA. 

12.  THE  accomplishments  of  photography  have  taught  the  public  to  be  very 
exacting.  It  is  expected  to  produce  results,  except  as  to  color,  about  as  the 
eye  sees  them  ;  and  some  exigeants  are  unhappy  because  no  poor,  starved  genius 
has  yet  given  us  "  photographs  in  colors." 

A  word  as  to  the  eye.  It  is  the  natural  camera  obscura,  lens,  diaphragm, 
and  all,  and  a  much  more  perfect  one,  too,  than  man  can  ever  hope  to  produce. 
The  eye  consists  of  four  coats  or  membranes,  viz.,  the  sclerotic  or  white  of  the 
eye,  A  A  A  A ;  the  cornea,  B  B,  a  transparent  medium  in  front  of  the  eye, 
through  which  we  see ;  the  choroid,  a  velvety  membrane  which  absorbs  the 
rays  which  pass  the  retina,  preventing  internal  reflection,  and  which  lines  the 
sclerotic  coat  on  the  inside.  The  retina,  R  R  R  R,  is  the  innermost  coat  of  all, 
and  is  simply  an  expansion  of  the  optic  nerve,  o  o,  which,  communicating 
directly  with  the  brain,  is  the  immediate  seat  of  vision ;  p  p  is  the  iris  of  the 
eye.  In  its  centre  is  a  circular  opening  called  the  pupil,  x.  Behind  the  pupil 


FIG.  3. 


FIG.  4. 


and  iris  is  the  crystalline  lens,  E,  a  firm  and  perfectly  transparent  body  through 
which  the  rays  of  light  pass  on  their  way  from  the  pupil  to  the  retina.  The 
posterior  chamber,  v  V,  is  filled  with  the  vitreous  humor  which  shapes  the 
whole  construction. 

12.  The  act  of  vision  is  accomplished  by  means  of  a  special  organ  or  pair  of  organs, 
the  eyes,  which  are  partly  physical,  or,  as  we  may  say,  instrumental  in  their  action, 
officiating  exactly  as  certain  lifeless  and  inorganic  structures,  such  as  we  artificially  con- 
struct, would  officiate,  in  collecting  and  distributing  the  light  rays ;  and  partly  physio- 

(31) 


32 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  5. 


13.  Now  put  your  camera  together,  and  you  will  see  how  much  it  resembles 
the  eye.  The  lenses  take  the  place  of  the  aqueous  humor  and  the  crystalline 
lenses ;  the  diaphragm  performs  the  functions  of  the  pupil  and  the  iris ;  the 
ground  glass  is  the  retina  of  the  camera. 

The  camera  must  receive  its  image  upon  a  flat  surface,  which  fact  constrains 
it  much,  especially  in  the  production  of  large  pictures.  Again,  as  the  object 
to  be  photographed  is  neared,  the  aperture  through  which  the  light  enters  must 
be  decreased  in  order  to  obtain  sharpness. 

logical  in  their  structure,  calling  into  play  those  conditions  of  life  about  which  we 
know  but  little,  and  which  we  can  in  no  wise  artificially  reproduce,  or  by  any  amount  of 
skill  ourselves  construct. 

In  the  eye  we  have,  in  the  first  place,  a  lens,  capable,  like  our  ordinary  lenses,  of  forming 
an  image  upon  the  inner  wall  of  the  eye-cavity,  or  retina. 

We  will  then  inquire,  in  the  first  place,  how  a  simple  lens  brings  about  such  a  result 
as  the  formation  of  an  image. 

The  diagram  shows  this  almost  without  need  of  further  explanation.     The  rays  from 

the  summit  of  the  object,  which,  without  the 
lens,  would  be  scattered,  are  each  differently 
bent  by  the  different  parts  of  the  lens  which 
they  encounter,  but  so  as  to  be  united  in  a 
single  point.  The  same  thing  happens  for 
each  other  point  of  the  object  and  its  emitted 
rays,  and  the  result  is  the  production  of  an 
image,  as  is  shown.  This  image,  moreover,  is  inverted ;  you  see  how  this  comes  by  a 
mere  glance  at  the  diagram. — PROF.  HENRY  MORTON. 

13.  Here  comes  in  the  second  part  of  the  eye's  constitution.  The  retina  is  not  simply 
a  dead  screen,  receiving  and  reflecting  the  various  impressions  of  light  which  fall  upon 
it.  It  is  a  forest  of  living  nerves,  which  not  only  can  distinguish  between  the  intensities 
and  colors  of  the  rays  which  touch  them,  but  also  recognize  the  direction  in  which  they 
come.  Thus,  the  inversion  of  the  image,  as  far  as  the  sensation  of  the  retina  is  concerned, 
does  not  exist.  If  the  retina  perceives  the  rays  from  the  summits  of  objects  as  coming 
down  to  it,  and  those  from  the  bases  as  coming  up,  and  thus  regarding  the  object  and  not 
the  (to  it)  invisible  image  formed  on  its  own  substance,  this  nerve-screen  sees  everything 
in  its  proper  position.  It  is  a  natural  error  to  think  of  the  eye  as  looking  at  the  image 
formed  on  its  own  retina,  but  a  little  thought  will  show  us  that  such  an  idea  is  parallel 
to  the  absurdity  of  hoping  to  see  one's  own  face  without  a  glass  or  equivalent  reflection. 
It  is  then  upon  the  sensitive  screen  of  the  retina  that  the  light  rays,  collected  and 
grouped  by  the  eye-lens,  make  their  impression.  The  nerves  of  this  organ,  like  those  of 
others,  have  certain  limits  to  the  range  of  their  coexistent  perceptions.  Thus,  just  as  we 
cannot  hear  a  whisper  in  the  presence  of  the  rattle  of  a  train,  or  taste  a  delicate  flavor  if 
mingled  with  a  bitter  draught,  so  we  cannot  perceive  a  faint  impression  of  light  in 
presence  of  another  of  far  greater  intensity. — PROF.  HENRY  MORTON. 


CHAPTER  Y. 

ABOUT   LENSES. 

14.  WHEN  Wilson's  Photographies  was  prepared  I  was  of  the  opinion  that 
photographers  were  so  well  informed  on  the  subject  of  lenses  that  it  would  be 
unnecessary  to  devote  more  than  a  very  few  pages  to  their  consideration.  I 
have  since  changed  that  opinion  on  account  of  the  general  ignorance  I  find 
concerning  photographic  optics,  and  so,  will  now  endeavor  to  spread  some 
light  on  the  subject. 

The  major  notes  are  elaborate  and  exhaustive.  They  appeared  serially 
in  the  Philadelphia  Photographer,  and  are  by  America's  most  distinguished 
optician.  With  such  help  I  hope  to  make  the  matter  quite  intelligible. 

Let  us  first  visit  a  manufactory  of  lenses  together  and  learn  the  mechanics 
of  optics. 

It  is  a  matter  of  primary  importance  that  the  glass  of  which  achromatic 

14.  I  am  often  asked,  "'In  what  respects  do  the  lenses  of  large  and  small  angle  differ?" 
If  you  have  a  tube  of  one  inch  diameter  and  one  inch  long,  it  would  be  a  square,  or 
have  an  angle  of  90°,  and  if  a  lens  were  placed  in  it,  it  would  show  a  picture  of  all  objects 
in  front  of  it  that  were  included  in  a  line  drawn  diagonally  from  the  back  to  the  front  of 
the  tube  and  continued  to  the  horizon.  The  same  lines  drawn  toward  the  ground-glass 
will  show  the  size  of  the  illuminated  circle  at  the  focus  o*f  the  lens.  To  illustrate,  suppose 
there  were  ninety  posts  or  trees  placed  at  equal  distances  apart :  if  you  place  a  lens  with 
an  angle  of  90°  at  such  a  distance  from  them  that  they  will  exactly  cover  the  circle,  and 
then  place  another  lens  of  45°,  but  of  the  same  focus,  only  forty-five  trees  will  be  seen, 
but  each  tree  will  be  exactly  alike  in  size.  In  this  case  each  tree  would  occupy  the 
space  of  one  degree,  and  if  the  lens  was  placed  at  half  the  distance  it  would  then  take 
the  space  of  two  degrees,  and  only  half  the  number  would  be  shown,  but  each  tree  would 
be  twice  the  size. 

From  this  it  will  be  seen  that  it  is  the  angle  of  the  lens  that  determines  the  size  of  the 
circle  of  illumination;  the  size  of  each  object,  if  taken  at  the  same  distance,  depending 
on  the  focus.  The  principal  reason  why  lenses  of  small  angles  are  used  is,  because 
opticians  are  enabled  to  make  the  work  with  comparatively  large  diaphragms,  and  con- 
sequently quicker.  The  diameter  of  the  lens  is  governed  by  the  judgment  of  the  maker, 
and  does  not  affect  the  focus  or  angle,  for  a  lens  of  any  diameter  if  placed  in  a  tube  of 
the  proper  length  will  give  any  angle  required. — R.  MORRISON. 

3  (33) 


34  WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

lenses  are  made  be  of  the  utmost  purity.  Up  to  within  a  recent  period,  the 
production  of  large  disks  of  optical  glass  so  free  from  defect  as  to  render  them 
adapted  for  achromatic  lenses,  was  looked  upon  as  impossible ;  for  even  with 
the  greatest  skill,  and  by  using  the  most  perfect  appliances  of  the  period,  defects 
of  a  nature  fatal  to  excellence  were  inherent  in  optical  flint  glass.  These 
defects,  to  which  the  best  flint  was  especially  subject,  consisted  in  a  want  of 
homogeneity  and  in  the  presence  of  striae,  knots,  threads,  and  other  defects  of 
a  similar  nature.  This  difficulty  in  the  way  of  obtaining  optical  glass  con- 
tinued until  about  seventy  years  ago,  when  M.  Guinand,  a  Swiss  clockmaker 
and  amateur  optician,  succeeded  in  solving  the  problem  -that  till  that  time  had 
engaged  the  attention  of  numerous  men  of  science  and  practical  glassmakers. 
Although  Guiuand's  discovery  has  thus  opened  the  way  to  the  successful  produc- 
tion of  large  disks  of  optical  glass,  yet  the  price  of  such,  even  in  its  rough 
form,  is  very  high.  This  partly  accounts  for  the  high  price  of  large  lenses. 
Before  a  disk  of  glass  is  sent  into  the  grinding-shop  it  is  subject  to  critical 

Let  me  try  to  explain  just  what  a  lens  is,  using  diagrams  to  assist  me. 
Light  is  propagated  in  a  straight  line.    We  cannot  see  around  a  corner.     If  a  ray 
of  direct  sunlight  passes  through  a  small  hole  of  any  given  shape  into  a  darkened 
chamber,  and  we  hold  a  screen  near  behind  the  aperture,  we  observe  a  bright  image  of 
the  shape  of  the  hole.     If  we  increase  the  distance  of  the  screen  and  the  aperture,  the 
image  of  the  hole  disappears  in  the  penumbra,  and  the  round  image  of  the  sun  takes  its 
place ;  and,  if  the  hole  is  small  enough,  you  will  see  not  only  the  image  of  the  sun,  but 
the  image  of  all  the  external  objects  will  appear  likewise.     This  is  one  of  the  most  inter- 
esting experiments,  and  its  explanation  is  easy.     Each  point  of  the  object  B  D  (Fig.  6) 
radiates  light  in  every  direction,  light  of  the  same  color  as  it  ap- 
FIG.  6.  pears  to  our  eye.     From  the  point  B,  no  light  can  reach  the  screen 

C,  except  through  the  small  aperture  A  at  B'\  but  if  the  aperture 
>£\  PIP      *s  innnitely  small,  no  other  point  of  the  object  can  send  its  rays  to 

B'.  The  same  is  true  for  every  other  point,  for  E  or  D,  for  in- 
stance; these  can  only  send  rays  to  their  respective  points  D'  and 
E',  and  so  on  with  the  rest,  and  an  inverted  image,  with  all  the 
natural  colors  of  the  object,  is  produced  on  the  screen.  If  we  now 
enlarge  the  hole,  different  points  of  the  object  would  reach  the 
same  place  upon  the  screen;  the  images  of  these  points  would 
overlap  each  other,  and  the  image  of  the  object  would  be  indistinct.  If  the  aperture  is 
sufficiently  enlarged,  the  image  disappears,  and  the  screen  is  illuminated  homogeneously, 
taking  only  a  tint  of  the  most  prominent  colors  of  the  objects.  Therefore,  the  smaller 
the  hole  is,  the  sharper  but  fainter  is  the  image.  The  size  of  the  image  depends  upon 
the  distance  of  the  object  from  the  hole,  and  also  upon  the  distance  of  the  screen  from 
the  hole.  This  primitive  camera  obscura  is  known  by  the  name  of  pinhole  camera. 


ABOUT    LENSES. 


35 


FIG.  7. 


examination,  to  permit  of  which,  two  small  portions  of  the  edge,  opposite  to 
each  other,  are  ground  flat  and  polished.  A  beam  of  polarized  light  is  now 
transmitted  through  the  disk,  which  is  then  examined  by  an  analyzing  prism. 
Now  we  are  where  the  rough  and  hard 
Avork  is  done,  and  as  each  stage  pro- 
gresses, there  is  less  hard  work  for  the 
muscles  and  more  for  the  brain.  After 
the  optical  glass  passes  muster,  it  is 
cut  into  pieces  of  proper  size  by  the 
"splitting"  machine,  diamond  dust 
being  used  for  the  persuasive  power. 

In  the  grinding  of  a  lens,  the  first 
operation  consists  in  "  roughing"  it,  or 
bringing  it  approximately  to  the  cur- 
vature it  is  ultimately  to  assume.  Fig. 
7  shows  in  which  way  this  is  effected. 
Cast-iron  blocks  turned  to  an  appro- 
priate degree  of  curvature,  either  con- 
cave or  convex,  according  to  the  nature 
of  the  surface,  together  with  coarse  emery  and  water,  form  the  tools  required 
at  this  stage.  When  the  glass  is  handed  to  the  rougher  it  is  round  in  shape, 

Light,  we  said,  is  propagated  in  a  straight  line ;  but  this  is  only  true,  when  it  con- 
tinues in  a  medium  of  the  same  density,  or  if  it  enters  a  medium  perpendicular  or 
normal.  But  if  a  ray  passes  from  one  medium  into  another  of  different  density  obliquely, 
its  direction  is  changed ;  it  is  refracted.  This  property  of  light  was  known  to  the  ancients 
about  eighteen  hundred  years  ago,  but  the  discovery  of  the  law  of  refraction  was  left  to 
Willebrod  Snell,  professor  in  the  University  of  Leyden,  1621.  I  will  briefly  state  this 
very  important  discovery,  which  elevated  optics  to  a  positive  science.  If  a  ray  of  light, 
R  (Fig.  8),  falls  perpendicularly  upon  a  plane  surface  of  a 
piece  of  glass,  A  B,  it  enters  the  glass  without  changing  its 
course,  in  a  straight  line,  R  D,  it  only  changes  its  velocity. 
But  if  a  ray,  m,  strikes  the  surface  at  E,  obliquely,  it  is 
refracted  to  n.  A  ray,  m/  is  refracted  to  n/.  Now  if  we 
erect  perpendiculars  from  the  points  m  and  n,  and  also  from 
the  points  m'  and  n',  to  the  normal  R  D,  and  divide  the 
length  o  m  by  n  p  and  also  divide  o/  vnf  by  n'  p/,  we  will  have 
in  both  cases  the  same  quotient,  or,  as  it  is  generally  ex- 
pressed :  the  sine  of  the  angle  of  incidence  divided  by  the 
sine  of  the  angle  of  refraction  is  a  constant,  whatever  the  angle  of  incidence  may  be. 
This  constant  quotient  is  called  the  index  of  refraction.  Different  media  have  different 


36          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

although  the  edges  are  rough,  having  previously  passed  through  the  hands 
of  another  staff  of  workmen,  who  chip  the  glass  into  something  near  the  size 
required. 

After  the  first  rough  grinding  has  been  effected,  the  embryo  lens  then  passes 
into  the  hands  of  the  "  lens-grinder/7  whose  function  it  is  to  follow  up  the  work 
of  the  rougher,  until  the  surface  is  brought  up  to  that  exquisite  degree  of  polish 
seen  in  the  best  lenses,  to  effect  which  a  great  degree  of  care  and  skill  is  required. 

indices  of  refraction ;  thus  a  diamond  has  a  higher  mdex  of  refraction  than  flint  glass, 
and  flint  glass  a  higher  one  than  crown  glass. 

Another  important  law  of  refraction  may  be  mentioned,  it  is  this :  The  incident  and 
refracted  ray  and  the  normal  are  situated  in  the  same  plane. 

If  a  ray  of  light  falls  on  a  parallel  piece  of  glass,  A  (Fig.  9),  perpendicularly,  it  will 
pass  through  it  in  a  right  line,  because  it  is  coincident  with  the  normal.  But  if  a  ray, 

FIG.  9.  FIG.  10. 


R' 

R,  strikes  the  glass  obliquely,  it  will  be  refracted  toward  the  normal,  N,  and  away  from 
it  when  leaving  it.  As  the  normals  N  and  N'  are  parallel,  so  must  the  incident  and 
refracted  ray  be  after  leaving  the  glass. 

Now  let  us  see  another  case,  where  the  two  surfaces  are  not  parallel,  but  form  an 
angle  with  each  other.  Such  a  medium  is  called  a  prism. 

R  o  (Fig.  10)  is  an  incident  ray;  the  ray  is  refracted  toward  the  normal  N,  along  o  o', 
and  by  leaving  the  prism  it  is  again  refracted,  but  this  time  from  its  normal  N,  as  it 
passes  from  a  denser  to  a  rarer  medium.  Therefore,  incident  rays  on  a  face  of  a  prism 
are  always  refracted  toward  the  base.  We  are  now  tolerably  well  prepared  to  see  what 
a  lens  is. 

A  lens  is  a  transparent  medium,  of  which  the  two  surfaces  are  either  both  curved,  or 
the  one  is  plane  and  the  other  curved.  If  the  curves  are  spherical,  the  lens  is  called  a 
spherical  lens;  if  the  curve  is  parabolic,  it  is  a  parabolic  lens,  etc.  Lenses  are  divided 
into  two  classes,  converging  and  diverging  lenses.  The  converging  lenses,  which  are 
thicker  in  the  centre  than  at  the  margin,  are:  The  double  convex  with  both  surfaces 
conxex ;  the  plano-convex  with  one  surface  plane  and  the  other  convex ;  and  the  convex- 
concave  (meniscus)  with  one  convex  and  one  concave  surface,  but  the  convex  of  the 
shortest  radius.  This  class  of  lenses,  which  may  all  be  used  as  magnifying  or  burning 
glasses,  are  called  convex  or  positive  glasses,  and  these  only  are,  strictly  speaking,  lenses. 
The  diverging  lenses,  which  are  thinner  in  the  centre  than  at  their  margin,  are :  The 


ABOUT    LBNSE8. 


FIG.  11. 


In  this  work  the  curved  tool  is  attached  to  the  top  of  a  post  (Fig.  11),  around 
which  the  workman  slowly  walks,  grinding  the  lens  by  the  pressure  of  both 
hands.  Not  only  must  he  by  walking  round 
the  posts  change  his  own  position  with  respect 
to  the  grinding-tool,  but  he  must  also  con- 
stantly change  the  position  of  the  lens  in 
relation  to  his  hand,  as  he  sweeps  it  over  the 
surface  of  the  tool.  In  this  way  are  avoided 
such  errors  of  figure  as  would  invariably 
occur  if  these  precautions  were  not  taken. 

The  piece  of  glass  which  is  to  serve  as 
one  of  the  lenses  of  a  combination,  is 
cemented  to  the  centre  of  the  "  tool/7  and 
around  it  are  cemented  six  other  pieces  of 
glass  called  "pads."  These  are  subjected 
to  the  same  amount  of  grinding,  but  are  of ! 
no  use  except  that  they  serve  as  bearings  to 
insure  the  exact  grinding  of  the  centre 
piece.  Thus  it  will  be  seen  that  a  photo- 
graphic lens  is  actually  the  centre  part  of  a  large  lens.  Very  often  a  number 
of  small  lenses  are  ground  together  at  once  on  one  tool.  In  no  other  way 
could  they  be  made  more  cheaply  than  larger  lenses,  for  the  amount  of  work 

double  concave,  with  both  surfaces  concave ;  the  plano-concave,  with  one  surface  plane, 
the  other  concave ;  and  the  concavo-convex,  with  a  concave  and  a  convex  surface,  the 
concave  having  the  shorter  radius.  These  diverging  lenses  are  called  negative  glasses. 

The  general  properties  of  lenses  which  are  of  importance,  are :   1.  The  principal  axis. 
2.  The  optical  centre.     3.  The  principal  and  conjugated  foci,  and,  4.  The  nodal  points 

FIG.  12. 


or  conjugated  centres.  A  straight  line,  drawn  through  the  centres  of  curvature  of  the 
spherical  surfaces  of  a  lens,  is  the  principal  axis  of  the  lens ;  if  the  one  surface  is  plane, 
the  axis  passes  through  the  centre  of  curvature  of  the  spherical  side,  and  is  perpendicular 
to  the  plane  surface.  In  all  lenses  the  principal  axis  must  go  through  the  middle  of  the 


38          WILSON'S  QUAKTER  CENTURY  IN  PHOTOGRAPHY. 

upon  them  is  just  the  same.  Having  been  ground  to  a  true  curve  the  next 
and  final  operation,  so  far  as  the  surface  of  the  lens  is  concerned,  is  to  bring 
it  to  a  high  degree  of  polish  or  gloss. 

The  lens  is  now  finished  in  all  but  the  "  edging/7  which  is  almost  of  equal 
importance  with  the  proper  grinding  of  the  surface,  because  on  the  edging  of  a 
lens  depends  the  correct  centring  of  the  combination.  To  effect  this  the  lens 
is  cemented  to  a  chuck  in  a  turning  lathe,  and  while  revolving  it  is  centred 
accurately  by  watching  the  reflection  of  a  lighted  candle  thrown  from  the 
surface.  Advantage  is  taken  of  the  soft  state  of  the  cement  to  bring  it  to  such 
a  state  as  to  show,  while  revolving,  the  image  of  the  flame  quite  stationary 
and  free  from  the  "wobble"  it  would  have  if  it  were  not  properly  centred. 
When  the  cement  is  hard,  a  workman  slowly  brings  in  contact  with  the  revolv- 
ing edge  a  piece  of  metal  charged  with  emery  and  water,  by  which  the 
asperities  are  removed  and  the  edge  made  square  and  accurate.  Fig.  14  repre- 
sents the  "  edger  "  holding  a  small  metallic  cup  in  his  hand,  wherewith  he  is 
finishing  the  edge  of  a  lens  that  has  been  ground  true. 

The  number  of  tools  or  curves  in  a  lens  establishment  is  very  great,  consist- 
ing of  upwards  of  two  thousand,  all  of  them  being  ground  with  such  accuracy 
that  the  curvature  of  each  is  known  to  the  fourth  place  of  decimals,  their 

lens,  that  it,  in  the  concave  through  the  thinnest,  and  in  the  convex  through  the  thickest 
part ;  otherwise,  we  have  a  prism  with  spherical  surfaces,  and  not  a  lens. 

Every  lens  possesses  a  point,  situated  in  its  principal  axis,  which  is  of  great  import- 
ance. A  ray  of  light  passing  through  that  point  will  undergo  equal  opposite  refraction, 
so  that  it  will  leave  the  lens  parallel  with  the  direction  in  which  it  entered.  If  we  con- 
sider the  lens  without  thickness,  we  simply  say,  rays  passing  through  the  optical  centre 
of  a  lens  undergo  no  refraction.  The  optical  centre  can  readily  be  found  by  drawing 
two  radii,  A  B  and  C  D  (Fig.  13),  from  the  centre  of  curvature  A  and  (7  of  its  surface, 
parallel  to  each  other,  but  oblique  to  the  axis  A  C,  then  connect  the  two  extremes  B  and 

D,  and  the  line  B  DOT  its  prolongation  will 

FIG.  13.  cut  the  principal  axis  in  0,  the  optical  cen- 

tre. If  the  lens  is  a  double  convex  one  of 
equal  radii,  the  optical  centre  is  the  centre 
of  the  lens,  or  its  centre  of  gravity.  Fig.  13 
is  such  a  lens.  Now  suppose  we  change 
one  curve  into  a  shallower  one,  of  longer 
radius,  it  is  evident  that  the  optical  centre 
is  shifted  towards  the  predominant,  more 

curved  side,  and  if  we  continue  to  make  that  side  shallower,  it  will  gradually  move 
towards  E,  until  the  surface  is  converted  into  a  plane,  in  which  case  the  optical  centre 
is  coincident  with  the  point  where  the  axis  cuts  the  curved  surface  E.  This,  we  will  see 


ABOUT    LENSES. 


39 


respective  radii  extending  from  thirty  feet  down  to  a  hundredth  of  an  inch. 
The  curvature  to  which  any  particular  lens  is  to  be  ground  is  calculated  mathe- 
matically to  suit  the  refractive  and  dispersive  ratios  of  the  glass  of  which  it  is 
to  be  formed ;  and  after  the  lens  is  finished,  if,  on  examination,  it  fails  to  come 
up  to  the  standard  of  sharpness,  the  particular  surface  which  exercises  control 
over  the  shortcoming  is  reground  in  a  tool  one  degree  deeper  or  shallower  in 
curvature. 


FIG.  14. 


FIG.  15. 


A  large  shop  in  every  factory  is  devoted  to  brass-turning  and  fitting.     In 
the  engraving,  Fig.  15,  is  seen  one  of  the  numerous  workmen  engaged  in 

afterwards,  is  an  important  point.  But  let  us  go  on  in  the  same  way,  still  reducing  that 
surface  by  making  it  a  concave  or  negative  one ;  it  is  clear  that  the  optical  centre  still 
marches  on,  moving  out  of  the  lens,  and  if  we  go  on  so  far  as  to  make  the  negative  curve 
equal  to  the  positive  one,  then  the  optical  centre  would  be  in  infinity,  and  if  we  disregard 
the  thickness,  we  have  no  lens,  but  a  non-optical  glass  like  a  watch-glass.  All  straight 
lines  passing  through  the  optical  centre  of  a  lens  are  called  secondary  axes.  The  next 
and  most  important  of  the  general  properties  of  a  lens  are  its  principal  focus  and  the 
conjugated  foci.  If  we  hold  a  convex  lens  towards  the  sun,  and  a  sheet  of  paper  at  a 
certain  distance  behind  it,  we  observe  a  bright  little  circle,  in  which  the  sunlight,  falling 
upon  the  lens,  is  collected ;  the  point  where  the  circle  is  smallest,  and,  therefore,  most 
intensely  illuminated,  is  called  the  principal  focus ;  that  is,  the  focus  for  parallel  rays. 
If  we  have  to  calculate  the  area  of  a  circle,  we  are  bound  to  look  at  the  circle  as  a 


40          WILSON'S  QUAKTER  CENTURY  IN  PHOTOGRAPHY. 

making  the  mount  of  one  of  the  new  small  symmetrical  lenses.  In  this  kind 
of  lens  the  Messrs.  Ross  have  effected  a  reformation  that  has  for  a  long  time 
been  much  desired  by  photographers,  viz.,  the  reduction  of  the  diameter  of  the 
lenses  to  the  smallest  possible  size,  and  the  causing  of  the  whole  series  of  twelve 
to  screw  into  one  flange,  one  cap  also  fitting  all  of  them.  It  would  be  well  if 
this  system  of  having  one  standard  flange  for  all  lenses  up  to  a  certain  size 
were  more  prevalent,  for  it  would  prove  a  boon  of  inestimable  value  to  pho- 
tographers. A  system  of  universality  of  screw  has  for  many  years  been  in 
use  in  connection  with  the  manufacture  of  object-glasses  for  microscopes ;  in 
whatever  country  microscopes  or  objectives  are  made,  they  are  fitted  to  one 
gauge.  The  varying  diameters  of  photographic  objectives  will  ever,  of  course, 
prevent  the  adoptiop  of  a  universal  flange  for  all  purposes ;  but  what  can  and 
ought  to  be  done  is  the  adoption  throughout  the  world  of  a  series  of  flanges,  as 
few  as  possible,  of  recognized  and  standard  sizes. 

When  two  achromatic  lenses  are  to  be  mounted,  they  are  first  of  all  placed  in 
a  trial  mount  so  adapted  as  to  permit  of  an  approximation  or  separation  of  the 

polygon  of  an  infinite  number  of  sides,  and  we  will  do  well  to  take  the  lens  as  an  infinite 
number  of  prisms,  more  so,  as  the  infinitely  small  portion  of  the  lens  struck  by  the  ray 
may  be  taken  for  a  tangent  plane.  Thus  a  converging  lens  may  be  considered  as  prisms 
united  at  their  bases,  and  a  diverging  lens  of  prisms  united  at  their  apices.  As  we  already 
know  that  prisms  refract  parallel  rays  toward  the  base,  it  is  easily  seen  why  converging 
lenses  refract  the  rays  R  R  (Fig.  16)  to  /,  and  that  diverging  lenses  diverge  the  rays 
RRtof. 

FIG.  16. 


The  distance  of  the  focus  from  the  lens  depends,  1st,  upon  the  curvature ;  2d,  upon  the 
refracting  power  of  the  material ;  and  3d,  upon  the  thickness  of  the  lens. 

Not  to  make  the  matter  unnecessarily  complicated,  we  will  take  the  supposition  that 
our  lenses  have  an  extremely  small,  or  no  thickness  at  all.  For  common  glass  of  an 
index  of  refraction  of  1.5,  calculation  shows  that  a  plano-convex  lens  has  a  focal  length 
of  the  diameter  of  the  sphere  of  which  the  lens  is  a  part.  A  double-convex  lens  of  equal 
radii  has  its  focus  half  that  distance,  or  equal  to  the  radius  of  the  surfaces.  If  the  double- 
convex  lens  of  equal  radii,  say  of  10  inches,  is  made  of  the  following  substances,  the 
thickness  neglected,  the  foci  would  be : 


ABOUT    LENSES.  41 

lenses.  The  test  object  is  a  watch  dial  placed  at  the  extreme  end  of  the  testing- 
room,  and  the  image  of  this  dial  is  examined  through  a  powerful  eyepiece. 
Unless  it  can  divide  the  closest  lines  upon  this  dial  the  lens  is  rejected.  In  this 
trial,  both  the  central  and  oblique  pencils  are  examined,  and  the  exact  amount 
of  separation  of  the  lenses  from  each  other  is  now  determined  by  experiment 
and  marked  upon  each  pair,  as  the  instructions  for  the  workman  to  whom  is 
intrusted  the  duty  of  the  final  adjustment  of  the  length  of  tube.  This  is  an 
operation  which  influences  materially  the  performance  of  the  lens,  when  it  is 
considered  that  so  nicely  poised  are  the  qualities  in  some  of  the  combinations 
of  more  recent  production,  that  a  deviation  of  a  fortieth  part  of  an  inch  from 
the  exact  distance  required,  and  determined  in  the  way  described,  will  affect  its 
performance  and  be  detected  by  the  manager  in  course  of  the  final  trial,  which 
is  made  after  the  lenses  have  been  finished. 

Thus  we  see  how.  much  care  and  skill  are  required  to  produce  even  the 
tiniest  tool  used  in  our  art,  and  how  costly  it  must  be. 

In  selecting  a  lens,  the  purchaser  is  helped  by  knowing  its  equivalent  focus 
and  its  included  angle  of  view. 

It  is  important  to  be  able  to  determine  the  equivalent  focal  length  of  a  com- 
bination, for,  until  that  is  done,  the  other  cannot  be  determined  with  exactness. 
I  propose  briefly  to  describe  the  best  methods  of  doing  both. 

Two  simple  methods  of  determining  the  equivalent  focus  of  a  combination 
have  been  pointed  out  by  Mr.  Grubb,  the  optician. 

For  common  glass,  index  of  refraction  1.5  =  focus  10  inches. 

For  flint  glass,  index  of  refraction  1.6  =  focus  8.33  inches. 

For  diamond,  index  of  refraction  2.439  =  focus  3.48  inches. 

We  see  that  the  diamond  lens  of  the  same  radius  has  a  focal  length  of  little  over  one- 
third  of  the  crown-glass  lens. 

We  have  now  seen  that  luminous  rays  from  a  point  infinitely  distant  are  collected  to  a 
single  point  in  the  axis,  the  principal  focus.  But  let  us  suppose  we  move  the  .luminous 
point  towards  the  lens,  to  make  the  rays  perceptibly  converging;  then  the  lens,  which 
was  strong  enough  to  bring  parallel  rays  to  the  point  wiiere  the  principal  focus  is  situated, 
is  not  strong  enough  to  bring  these  diverging  rays  to  the  same  point,  but  they  will  cross 
the  axis  at  a  point  farther  removed  from  the  lens ;  and  as  the  radiating  luminous  point 
is  moved  nearer  to  the  lens,  the  farther  off  from  the  lens  they  will  cross  the  axis ;  by 
moving  still  on,  we  come  to  a  point  where  the  radiating  point  and  the  point  where  the 
rays  cross  the  axis  on  the  opposite  side  are  equally  distant  from  the  lens.  In  this  case 
the  radiating  point  and  the  rays  where  they  cross  the  axis  are  nearly  four  times  the 
distance  of  the  principal  focus  apart.  For  ordinary  purposes,  this  affords  a  ready  means 
to  determine  tho  principal  focus  of  a  lens.  But  let  us  move  on  still  nearer  to  the  lens, 


42          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

a.  Determine  the  central  point  of  your  focussing-screen,  by  drawing  diago- 
nals from  the  corners.  Select  two  distant  objects,  and  bring  them  into  focus  on 
your  ground-glass,  so  that  the  intersection  of  the  diagonals  shall  be  midway 
between  them.  The  camera  is  supposed  to  be  placed  upon  a  smooth  table  with 
a  sheet  of  white  paper  under  it.  Measure  with  a  compass  the  distance  between 
the  two  distant  objects,  as  they  appear  on  the  ground-glass.  Now  turn  the 
camera  so  that  one  of  the  distant  objects  shall  correspond  with  the  central 
point,  and  run  a  pencil  along  the  side  of  the  camera  so  as  to  mark  its  position 
on  the  paper.  Next,  rotate  the  camera  until  the  central  point  corresponds  with 
the  other  distant  object,  and  draw  a  line  along  the  side  of  the  camera  again. 
These  two  lines  (produced  if  necessary)  will  form  an  angle.  You  have  mea- 
sured with  compasses  the  distance  between  the  images  of  the  two  objects  on  the 
ground-glass.  Set  this  off  so  that  it  may  connect  the  two  lines  drawn  on  the 
paper,  forming  therewith  an  isosceles  triangle,  of  which  it  is  the  base,  and  the 
two  lines  drawn  are  the  legs.  The  length  of  either  of  these  two  lines  is  the 
equivalent  focal  length  of  the  combination. 

This  method  is  of  universal  application  to  all  sorts  of  lenses.  The  second 
method  is  intended  for  portrait  lenses  only. 

Draw  on  the  ground-glass  two  vertical  lines  several  inches  apart,  say  about 
half  the  focal  length  of  the  lens  or  anywhere  thereabouts.  Focus  a  distant 

and  the  focus  on  the  other  side  will  continue  to  move  farther  away  until  we  reach  the 
principal  focus  this  side ;  then  the  rays  will  emerge  parallel  on  the  other  side.  By  over- 
stepping that  point,  the  rays  will  emerge  diverging.  These  variable  distances  of  the 
luminous  point  and  the  focus  on  the  other  side,  are  called  the  conjugated  foci.  There 
remains  to  be  mentioned  another  important  general  property  of  lenses,  the  nodal  points, 
or,  as  they  are  sometimes  called,  the  centres  of  a-dmission  and  emission. 

M  is  a  double-convex  lens  of  equal  radii,  o  is  its  optical  centre.     Any  ray  passing 
through  the  optical  centre,  as  R  R,  emerges  on  the  other  side  parallel  to  its  first  direc- 
tion, R/  R',  as  explained  before.     If  we  now  prolong  R  and  R  in 
FIG.  17.  their  first  direction,  they  will  meet  at  a  point  P,  the  one  nodal 

point,  or  the  centre  of  admission,  and  if  the  emerging  rays  are 
also  prolonged,  they  will  converge  to  a  point  P/,  the  other  nodal 
point,  or  the  centre  of  emission.  We  recollect  that  in  the  pin- 
hole  camera  the  size  of  the  image  compared  with  that  of  the 
object  is  exactly  in  the  same  proportion  as  the  distance  from  the 
screen  to  the  hole  is  to  the  distance  of  the  object  from  the  hole. 
These  distances  represent  the  two  conjugated  foci,  as  there  is  no 
deviation  of  the  rays  from  a  straight  line,  and  the  two  triangles, 

which  are  to  be  compared,  meet  with  their  apices.  But  if  we  have  a  bi-convex  lens 
(Fig.  19)  and  A  B  an  object,  C  D  its  image,  it  is  clear  that  the  conjugated  foci  are  to  be 


ABOUT    LENSES. 


43 


FIG.  18. 


object,  on  the  ground-glass,  and  turn  the  camera  until  one  of  the  lines  passes 
through  its  centre.  Draw  a  Hne  along  the  side  of  the  camera  upon  the  paper 
as  before.  Rotate  the  camera  until  the  other  line  passes  through  the  centre  of 
the  object,  and  draw  another  line  along  the  side  of  the  camera.  Produce  these 
lines  till  they  meet,  forming  an  isosceles  triangle  with  the  distance  between 
the  two  parallels  on  the  ground-glass  for  a  base.  As  before,  the  length  of  one 
of  the  legs  will  give  the  equivalent  focal  length  sought.. 

The  annexed  (Fig.  18)  is  suggested 
by  Mr.  M.  Carey  Lea. 

A  and  B  are  the  distant  objects,  from 
which  the  rays  L  and  U  are  brought  to 
a  focus  at  P  Pf  on  the  ground-glass, 
equidistant  from  the  centre  (7,  and 
the  distance  P  Pf,  is  measured  with 
compasses.  (These  rays  are  what  are 

termed  "  parallel  rays/'  the  distance  of  the  object  being  so  great,  in  comparison 
with  the  focal  length,  that  they  may  be  considered  parallel.)  The  camera  is 
now  turned  until  the  image  of  A  moves  from  P  to  C,  and  the  line  0  P  is 
drawn  along  the  edge  of  the  camera  on  the  paper  underneath.  Then  the 
image  Pf  of  the  object  B  is  similarly  brought  to  C,  and  the  line  0  Pf  is 
drawn.  Next,  the  triangle  0  P  Pf  is  .completed  by  setting  off  the  base  P  Pf, 
and  the  legs,  0  P,  0  P',  are  evidently  the  focal  distance.  (For  simplicity  of 

measured  from  the  nodal  points  Pand  P,  and  the  two  conjugated  foci  are  F  P  and  F  P, 
showing  how  erroneous  it  is  to  measure  the  foci  either  from  the  surface  of  the  lens,  or 
from  the  optical  centre.  In  a  meniscus,  the  one  nodal 
point  is  situated  outside  of  the  lens,  and  the  other  one 
inside  of  the  lens.  But  in  a  plano-convex  lens  the  op- 
tical centre  as  well  as  the  nodal  point  are  situated 
where  the  principal  axis  crosses  the  curved  side.  The 
plano-convex  lens  is  therefore  the  only  lens  of  which 
the  focal  length  can  be  measured  directly.  If  the 
plane  side  is  placed  towards  a  very  distant  object, 
the  distance  of  the  curved  side  to  the  image  is  the 
principal  focus. 

It  is  often  necessary  to  know  the  focal  length  of  a  lens 

or  a  combination  of  lenses,  especially  in  photography ;  but  if  no  plano-convex  lens  of 
known  focal  length  is  at  hand,  for  the  purpose  of  comparing  the  size  of  the  image,  the 
following  way  may  be  adopted:  first,  focus  the  lens  for  a  very  distant  object,  on  a  screen, 
and  mark  the  position  of  the  screen.  Do  not  move  the  lens,  but  place  a  bright  object 


FIG.  19. 


44 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


figure,  a  single  lens  is  taken ;  the  principle  is  evidently  exactly  the  same  for  a 
combination.) 

b.  The  same  figure  will  serve  to  illustrate  the  second  method.  In  this,  the 
two  points  P  and  Pf  are,  first,  arbitrarily  marked  on  the  ground-glass  so  that 
the  image  of  a  single  distant  object,  A,  shall  fall  on  P,  and  the  line  0  P  is 
drawn  on  the  paper  by  the  side  of  the  camera.  The  camera  is  then  rotated  till 
the  image  of  the  same  distant  object  falls  on  the  mark  P',  and  the  line  0  Pf  is 
obtained.  The  construction  in  this  case  is  evidently  the  same  as  before. 

Having  found  the  equivalent  focus,  by  either  of  these  methods,  it  is  easy  to 
determine  the  included  angle  of  view.  Fig.  20. 


FIG.  20. 


FIG.  21. 


Let  A  B  be  the  diameter  of  the  circle  of  light  given  by  the  lens,  which,  of 
course,  is  easily  determined  by  measurement,  and  C  D  the  equivalent  focus  as 
found ;  we  want  the  angle  AD  B. 

AC 
We  have  A  C=  D  C  Tan.  A  D  C,  Tan  A  D  0=  -^,  from  whence  the  angle, 

AD~B=2ADC,  is  easily  computed  by  logarithms. 

about  twice  the  focus  of  the  lens  in  front  of  it,  as  near  as  you  can  suppose ;  now  move 
the  screen  about  the  same  distance  from  the  lens  as  the  object  was  placed,  and  focus 
thereupon.  If  you  find  the  object  and  image  not  of  exactly  the  same  size,  move  object 
and  screen  accordingly,  and  focus  sharp,  until  the  object  and  image  are  precisely  of  the 
same  size ;  mark  the  position  of  the  screen  again,  and  the  distance  of  the  first  and  second 
mark  is  the  focal  length  of  the  lens,  or  the  equivalent  lens  of  a  combination  of  lenses. 

We  are  now  acquainted  with  the  most  important  properties  of  a  lens,  and  it  remains 
only  to  be  said,  that  all  combinations  of  lenses  have  precisely  the  same  general  properties 
as  single  lenses. 

We  come  now  to  a  somewhat  more  complicated  and  difficult  part  of  the  subject,  the 
aberrations  of  lenses  and  the  modes  of  their  correction.  So  far  we  have  supposed  the 


ABOUT    LENSES.  45 

The  law  which  fixes  the  focal  length  of  a  meniscus  objective  is  different  from 
that  in  the  case  of  the  combination.  In  the  meniscus  tJie  apex  of  the  emitted 
cone  is  coincident  with  the  optical  centre,  and  from  that  optical  centre,  not  the 
actual  centre,  the  focal  length  must  be  measured. 

In  Fig.  21,  let  0  Of  be  the  centre  of  curvature  of  the  faces  of  the  meniscus 
lens,  exposed,  of  course,  with  its  concave  surface  toward  the  light.  Let  a  ray 
of  light,  jR,  be  incident  upon  the  first  surface  at  8  at  such  an  angle  that  it  will, 
after  refraction,  pass  through  the  optical  centre  CJ  which,  in  the  case  of  a 
meniscus  presented  with  its  concave  surface  to  the  object,  as  usual,  is  always 
outside  of  the  lens  on  the  convex  side.  It  will  at  8  be  deflected  toward  the 
normal,  0  N9  and  reach  the  second  surface  at  Sf,  where  it  will  be  deflected 
away  from  the  normal,  0'  JV,  of  the  exterior  curve,  and  will  pass  through  the 
centre  C.  As  there  is  no  second  lens,  it  will  suffer  no  further  deflection,  and 
therefore  the  optical  centre  is  in  this  case,  also,  the  apex  of  the  cone  of  emitted 
rays.  If  the  ray  R  8  be  produced,  it  will  cut  the  axis  at  a  point,  A,  which 
is  the  apex  of  the  cone  of  entering  rays.  The  distance  from  the  point  C  (and 

lens  as  very  small,  in  relation  to  its  focal  length,  and  that  with  such  a  lens  all  rays  coming 
from  one  point  are  refracted  by  the  lens  in  one  point  again ;  but  in  practical  optics  such 
is  not  the  case,  as  lenses  of  very  large  aperture  are  often  required  in  modern  optical 
instruments,  and  the  rays  coming  from  one  point  are  no  longer  collected  in  one  point, 
and  this  optical  defect  occasions  the  different  aberrations.  For  over  a  century  the  cor- 
rection of  these  aberrations  employed  our  most  eminent  mathematicians,  as  Euler, 
Fraunhofer,  Herschel,  Fresnel,  Littrow,  Gauss,  Airy,  Petzval,  and  others. 

The  most  important  of  these  aberrations  are  spherical  aberration,  chromatic  aberration, 
curvature  of  field,  distortion,  and  astigmation. 

The  marginal  parallel  rays  R  R  (Fig.  22),  passing  through  a  convex  lens  L,  cross  the 
axis  at  f  nearer  to  the  lens  than  the  more  central  ones  R'  It',  which  cross  at/.  This  is 
a  result  of  the  spherical  surface  of  the  lens,  and  is  called  sphered!  aberration. 

If  we  present  a  convex,  short-focus  lens  to  solar 
rays,  and  produce  a  sharp  image  of  the  the  sun  on  a 
piece  of  white  paper,  we  will  find  that  the  image  at 
/,  which  is  the  one  made  by  the  central  rays  (and 
therefore  is  the  sharpest),  is  surrounded  by  a  halo, 
a  b,  which  is  what  we  call  the  lateral  spherical  aber- 
ration. This  halo  is,  as  you  see,  produced  by  the 
shorter  marginal  rays  R  R,  after  crossing  the  axis, 
diverging,  and  is  also  called  the  circle  of  aberration. 

/'/,  the  distance  of  the  difference  of  the  central  and  marginal  rays,  constitutes  the  lon- 
gitudinal aberration.  The  least  spherical  aberration  is  where  the  two  cones  intersect 
each  other  between /'  and/.  This  aberration  is  called  positive. 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


not  from  the  actual  centre  of  the  lens)  to  the  focussing-screen  will  be  the 
equivalent  focal  length. 

In  order  to  show  how  incorrect  is  the  common  mode  of  measuring  the  focal 
length  of  a  meniscus  from  the  back  surface  of  the  lens,  it  is  simply  necessary  to 
observe,  in  Fig.  12,  how  far  the  position  of  the  optical  centre  C  is  removed 
from  the  actual  centre  of  the  lens.  It  will  be  seen  how  far  behind  the  back 
surface  it  is  situated. 

The  "  back  focus  "  which  is  so  much  used  in  describing  lenses,  and  which  is 
the  distance  from  the  posterior  surface  of  the  back  lens  to  the  focussing  surface, 
is  liable  to  this  very  serious  objection,  that  it  is  not  merely  a  very  rough 
approximation,  but  that  its  incorrectnesses  are  in  opposite  directions  in  different 
lenses.  The  "  back  focus  "  of  a  meniscus  is  always  materially  longer  than  the 
true  focus,  whilst  it  is  shorter  than  the  true  one  in  the  case  of  a  combination 
objective. 

15.  The  photographer  should  not  expect  too  much  from  a  lens.  I  am  often 
asked  to  point  out  a  universal  lens  which  would  answer  for  all  purposes — 
equally  serviceable  for  portraiture,  landscapes,  architectural  objects,  etc.;  if 
possible,  such  a  lens  is  to  be  wide-angled  and  quick-acting. 

That  such  a  lens  does  not  exist  I  hardly  need  to  mention  here.     A  good 

If  converging  rays  R  R  and  R'  R'  (Fig.  23),  which  we  suppose  would  be  collected  in 
the  point  o,  fall  on  a  concave  lens,  the  marginal  rays  R  R  are  refracted  stronger  than  the 

more  central  ones  R'  R',  consequently  R  R  will 
cross  the  axis  farther  from  the  lens,  at/',  than  the 
more  central  ones,  R/  R/ ',  which  cross  the  axis  at 
/.  In  this  case  the  spherical  aberration  is  of  the 
opposite  character,  and  is  called  negative  aberra- 
tion. It  is  evident,  from  the  foregoing,  that  spher- 
ical aberration  varies  with  the  aperture  of  the  lens 
and  the  material  of  which  the  lens  is  made. 
Therefore,  the  larger  a  lens  is  in  proportion  to 
its  focal  length,  the  greater  its  spherical  aberra- 
tion. A  lens  of  an  aperture  of,  say  -^th  of  its 

focal  length,  has  no  perceptible  spherical  aberration.  The  longitudinal  spherical  aber- 
ration increases  as  the  square  of  the  diameter  of  its  aperture,  and  inversely,  as  its  focal 
length,  while  the  lateral  aberration  increases  as  the  cube  of  its  aperture,  and  inversely, 
as  the  square  of  its  focal  length. 

Thus,  if  we  have  two  lenses  of  the  same  curvature,  made  of  the  same  material,  but  the 
one  of  twice  the  aperture  of  the  other,  the  longitudinal  aberration  of  the  larger  one  is 
four  times  as  great,  and  the  lateral  or  circle  of  aberration  is  eight  times  as  great  as  that 
of  the  smaller  one. 


FIG.  23. 


ABOUT    LENSES.  47 

photographer  will  always  need  several  lenses  when  he  wants  to  do  more  than 
to  make  portraits ;  all  that  he  can  do  is  to  accomplish  with  a  few  lenses  as 
much  as  possible.  I  knew  a  photographer  who  was  often  called  upon  to  take 
architectural  views — a  work  in  which  the  demand  for  actinic  power,  form, 
angle  of  view,  and  flatness  of  the  picture  is  very  manifold.  In  order  to  satisfy 
all  these,  he  unscrewed  the  lenses  from  the  different  objectives  and  recombined 
them  in  pasteboard  tubes  in  various  manners.  For  instance,  the  front  lens  of 
a  Steinheil  with  the  back  lens  of  a  Voigtlander  portrait,  or  the  frant  lens  of  an 
Orthoscope  with  the  back  lens  of  a  Hermagis  portrait,  etc.  He  then  con- 
structed on  the  spot,  the  combination  which  gave  on  the  ground-glass  the  most 
suitable  picture.  It  is  evident  that  in  spite  of  stops,  many  optical  errors  cannot 
be  avoided,  but  it  shows  what  can  be  done  with  a  little  common  sense  and  a 
little  optical  knowledge,  for  his  architectural  views  rank  amongst  the  best  that 
I  have  seen. 

In  regard  to  optics,  there  remains  in  fact  much  to  be  desired,  although  often 
shortcomings  are  attributed  to  the  lens  which  really  belong  to  the  operator. 
Here  is  an  original  case  :  A  man  took  the  picture  of  a  building,  and  obtained 
two  images  instead  of  one ;  one  picture  was  sharp  and  clearly  defined,  while  the 
outlines  of  the  other  were  indistinct.  He  repeated  the  experiment  several 
times,  always  with  the  same  result.  Supposing  the  fault  to  be  with  the  lens, 
he  removed  it  and  substituted  another ;  the  result  remained  the  same.  Finally 
he  discovered  that  a  small  hole  in  the  front  board  of  the  camera  was  the  cause 

If  two  lenses  have  the  same  aperture,  but  the  focal  length  of  the  one  is  twice  as  long 
as  that  of  the  other,  the  longer  one  has  only  one-half  the  longitudinal  and  one-fourth  the 
lateral  aberration.  As  a  lens  made  of  a  denser  medium,  say  of  heavy  flint  glass  or 
diamond,  requires,  for  the  same  focal  length  a  longer  radius  of  curvature  than  one  made 
of  crown  glass,  it  follows  that  its  spherical  aberration  is  less. 

The  single  lens  of  ordinary  glass,  having  an  index  of  refraction  of  1.5,  has  the  form  of 
lost  spherical  aberration  when  it  is  a  crossed  convex  lens  with  the  surfaces  of  different 
radii,  the  proportions  of  the  radii  depending  on  the  index  of  refraction  of  the  material  of 
which  the  lens  is  made.  For  ordinary  glass,  index  1.5,  the  radii  are  as  1  to  6,  the  shortest 
curve  towards  parallel  rays.  The  best  form  for  a  lens  made  of  flint  glass,  index  1.6,  is 
the  plano-convex,  and  for  diamond,  is  a  meniscus,  of  which  the  convex  radius  is  to  the 
concave  as  2  to  5,  for  radii  of  curvature. 

We  see  that  in  lenses  of  wide  apertures  the  spherical  aberration  may  be  considerable 
enough  to  interfere  with  the  sharpness  of  the  image,  especially  if,  as  in  a  telescope  and 
microscope,  the  image  with  all  its  errors  is  magnified  by  an  eyepiece.  Let  us  now  see 
what  means  we  have  to  reduce,  correct,  or  destroy  the  spherical  aberration.  The  most 
simple  way  is  by  the  use  of  a  diaphragm.  A  diaphragm  is  a  non-transparent  plate,  com- 


48 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


of  all  the  trouble.  A  small  hole  will  produce  by  itself  an  image  on  the  ground- 
glass  (pinhole  camera),  and  in  this  instance  it  acted  like  a  second  lens. 

Lenses  vary,  even  when  of  the  same  advertised  angle  and  focal  length. 
Especially  is  this  so  with  wide-angle  lenses. 

"  Do  wide-angle  lenses  give  true  perspective  ? "  therefore  remains  a  query 
but  partly  answered. 

It  is  obvious  that  a  drawing  on  a  surface,  of  objects  situated  in  different 
planes,  can  be  made  a  correct  representation  for  only  one  position  of  the  eye 
with  reference  to  it.  For  when  we  vary  the  position  of  the  eye,  previously 

monly  made  of  metal,  perforated  in  the  centre  (Fig.  24).  A  B  is  such  a  diaphagm ;  c  d, 
the  aperture  of  it.  If  this  diaphragm  is  placed  in  contact  with  the  lens,  it  is  nearly 
equal  to  reducing  the  lens  to  the  size  of  the  aperture  of  the  diaphragm,  and 
as  we  have  seen  before,  the  spherical  aberration  is  considerably  reduced,  but 
the  light  also.  If  the  loss  of  light  is  of  little  consequence,  this  mode  of 
reducing  spherical  aberration  may  be  adopted  with  advantage.  Another 
way  of  reducing  the  spherical  aberration  is  by  adopting,  for  a  given  aperture 
and  focal  length,  two  or  more  lenses  of  the  same  aperture,  and  the  same 
equivalent  focus  of  the  single  lens.  We  have  seen  before,  that  two  lenses  of 
the  same  aperture,  but  their  focal  length  as  1  to  2  to  each  other,  the  longer 
one  has  only  one-fourth  of  the  spherical  aberration  of  the  shorter  one.  Lens 
M  (Fig.  25)  has  its  focus  at/.  The  lenses  L  and  .2^  are  of  the  same  aperture 
as  M,  but  each  has  twice  the  focal  length  of  the  lens  M;  therefore  each  has 
only  one-fourth  the  spherical  aberration  of  M;  but  L  and  N  together  have  the  same 
focal  length  as  M,  and  as  their  apertures  are  alike,  the  combination  L  jVhas  only  one- 
half  the  lateral  spherical  aberration  of  the  lens  M.  But  by  this 
mode  of  correcting,  it  is  not  possible  to  destroy  the  spherical  aber- 
ration completely,  although  it  is  stated  in  some  works  on  optics, 
that  a  combination  of  two  convergent  lenses  was  calculated  by  Sir 
John  Herschel,  and  said  to  be  free  from  spherical  aberration.  This, 
however,  is  a  mistake,  which  Herschel  himself  has  rectified  in  his 
memoirs. 

We  now  come  to  the  most  important  method  of  correcting  spher- 
ical aberration,  that  is,  by  a  second  lens  of  opposite  character. 
Suppose  we  want  to  correct  the  spherical  aberration  of  the  positive 
lens  L  (Fig.  26)  along  its  axis.  //'  is  the  longitudinal  spherical 
aberration  of  the  rays  A  B,  parallel  to  the  axis  A,  at  the  margin  of 
the  lens,  and  B  near  the  centre  of  the  lens  L.  If  we  combine  this 
lens  with  a  convergent  negative  lens  M,  it  is  not  difficult  to  see,  by 
what  we  learned  before,  that  the  lens  M  has  very  little  power  to 
change  the  direction  of  the  ray  bf,  and  bring  it,  say,  to  F;  but  it 
will  greatly  change  the  course  of  Af,  so  as  to  bring  it  also  to  F.  since  the  prismatic  form 
is  greater  at  the  margin  than  at  the  centre.  Of  course,  the  form  of  the  lens  must  be 


ABOUT    LENSES.  49 

fixed  upon,  before  the  objects  themselves,  their  relative  positions  change,  and 
the  picture  would  have  to  be  altered  correspondingly  to  be  right  for  the  new 
position.  So  when  we  vary  the  eye  from  its  proper  place,  before  a  correct 
picture,  we  have  distortion  as  a  natural  consequence. 

It  is  found,  in  practice,  that  when  a  drawing  is  made  to  include  from  20°  to 
30°,  much  latitude  may  be  allowed  in  the  position  of  the  eye  without  the  dis- 
tortion being  apparent.  For  this  reason  such  pictures  are  most  readily  viewed. 
As  we  increase  the  angle  of  view  the  necessity  for  placing  the  eye  in  its  proper 
position  becomes  more  obvious,  and  when  we  reach  an  angle  of  90°,  the  eye 
must  be  placed,  with  considerable  accuracy,  at  a  distance  from  the  picture  equal 
to  one-half  its  width,  else  the  amount  of  distortion  may  be  considerable. 

We  will  now  consider  t|ie  case  of  photographing  a  row  of  houses,  of  equal 
size,  with  a  wide-angle  lens.  The  camera  is  supposed  to  be  opposite  the  central 
house,  with  the  plate  parallel  to  the  row.  It  is  objected  that  the  resulting 
picture  will  give  the  houses  all  of  the  same  size,  when  we  measure  them  on  the 
plate. 

After  what  has  been  said  about  the  necessity  for  placing  the  eye  in  the  right 
position,  a  little  consideration  will  show  this  is  as  it  should  be,  for  the  proper 
perspective  effect  is  produced  by  the  picture  itself,  the  extreme  houses  in  the 
picture  being  more  distant  from  the  eye  than  the  central  one,  in  the  same  pro- 
suited  to  the  material  of  which  it  is  made ;  for  our  present  purpose,  both  of  the  lenses 
may  be  made  of  the  same  glass,  but  it  is  much  better  if  the  lens  M  is  made  of  a  denser 

FIG  26. 


f 


glass,  as  we  shall  soon  see,  that  the  same  lens  may  be  used  to  correct  the  chromatic  aber- 
ration also.  By  this  methot"  the  spherical  aberration  can  not  only  be  corrected,  but  the 
marginal  rays  can  be  made  to  cross  the  axis  farther  from  the  lens  than  the  central  ones; 
in  this  case  the  lens  is  called  over-corrected,  while  if  not  enough  corrected,  it  is  called 
under-corrected.  So  far  we  have  considered  the  aberration  of  rays  parallel  with  the  axis. 
But  magic  lanterns,  photographic  and  microscopic  lenses  include  angles  from  40°  to  175  , 
and  the  foregoing  is  only  applicable  to  a  narrow  angle  near  the  centre  of  the  lens.  If  a 
lens,  corrected,  parallel  to  its  axis,  for  spherical  aberration,  is  struck  obliquely  by  parallel 

4 


50 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


portion  as  when  viewing  the  houses  themselves  from  the  point  where  the  view 
was  taken. 

It  is  for  the  reason  just  mentioned,  that  perpendicular  and,  consequently, 
parallel  lines  in  nature  are  represented  by  parallel  lines  in  a  perspective 
drawing ;  though,  in  looking  up,  as,  for  instance,  at  the  sides  of  a  high  building, 
the  sides  apparently  converge. 

If,  with  the  camera  before  the  window,  the  lens  be  kept  constantly  at  the 
same  point,  while  the  camera  is  turned  so  as  to  receive  the  image  of  the  window 
on  different  parts  of  the  ground-glass  in  succession,  it  will  be  seen  that  this 
image  expands  as  it  moves  from  the  centre,  and  at  the  borders  of  the  plate 
becomes  considerably  larger.  Let  us  carry  this  experiment  further,  and  catch 
the  image,  projected  under  the  above  conditions,  on  different  parts  of  a  sensitive 
plate,  and  develop  it.  Now  return  the  plate  having  the  images  to  the 
camera,  and,  taking  off  the  lens,  place  the  optical  centre  of  the  eye  at  the  point 
previously  occupied  by  the  diaphragm.  Now  all  these  images  will  appear  of 
the  same  size.  This  should  be  the  case,  for  they  were  taken  from  the  same 
point,  and  each  representation,  if  truthful,  should  subtend  the  same  angle, 
provided  the  eye  is  in  correct  position. 

To  secure  lenses  as  perfectly  correct  as  possible  is  the  aim  of  the  buyer. 

rays,  but  the  longitudinal  aberration  is  different  for  two  diameters,  and  is  greatest  in  the 

plane  laid  through  the  axis  of  the  lens  and  the  radiating  point,  then,  the  circle  of 

aberration  becomes  the  more  elongated,  as  the  more 
obliquely  and  marginally  the  light  strikes  the  lens, 
until  it  terminates  in  a  point  at  their  extreme  mar- 
gin, which  is  known  as  the  coma. 

L  is  a  plano-convex  lens ;  H  F,  an  axis  through 
the  optical  centre,  making  a  considerable  angle  with 
the  axis  D  E.  R  and  R'  are  parallel  margin  rays. 
The  ray  R  will  cut  the  axis  at  F,  and  R/  farther  off 
at  F,  and  therefore  the  image  of  a  luminous  point  is 
no  more  a  point,  but  appears  elongated,  and  in  the 
extreme  has  the  shape  of  a  coma,  which  in  this  case 
is  directed  downwards.  If  we  reverse  the  lens,  as  in 
the  next  figure,  so  that  the  incident  rays  fall  on  the 
convex  side,  the  coma  is  directed  outwards.  We  see 
we  have  here,  by  reversing  the  lens,  opposite  comas  ; 
and  by  such  lenses  of  opposite  character  properly  com- 
bined at  the  right  distance,  and  furthermore,  by  the 

use  of  a  diaphragm  at  the  proper  place,  the  spherical  aberration  for  oblique  rays  can  be 

reduced  to  a  small  amount. 


FIG.  27. 


ABOUT    LENSES. 


51 


The  first  condition  of  non-distortion  I  believe  to  be  this :  That  the  pencils 
before  and  after  transmission  through  the  lens,  are  in  the  same  right  lines ; 
pencils  in  a  strict  sense,  not  rays,  but  such  small  sheafs  of  rays  as,  emanating 
from  single  points  of  the  object,  are  focalized  by  minute  elements  of  the  lens  so 
as  to  produce  corresponding  parts  of  the  image. 

If  the  lines  of  direction  in  these  various  pencils  before  and  after  transmission 
are  parallel  or  coincident,  it  is  clear  that  one  important  condition  of  non- 
distortion  will  be  fulfilled,  and  that  the  relative  dimensions  or  angular  distances 
of  objects  and  parts  of  objects  will  be  maintained ;  and  that  wherever  the 
tangent  plane,  which  represents  the  plane  of  foci,  is  situated,  it  will  receive  a 

So  far  we  have  considered  a  ray  of  light,  refracted  by  a  transparent  medium,  to  be  still 
a  single  ray.  Such  would  be  the  case  were  the  white  ray  of  light  of  a  single  homogeneous 
color;  but  what  we  call  a  white  light  is  composed  of  different 'colored  rays,  which,  by 
passing  through  a  refracting  medium,  are  refracted  in  different  degrees.  This  is  the 
source  of  another  aberration  of  even  more  importance  than  the  spherical  aberration — the 
chromatic  aberration.  By  passing  a  beam  of  white  light,  B  (Fig.  28),  through  a  prism, 
it  is  not  only  refracted,  but  decomposed  into  seven  colors,  red,  orange,  yellow,  green,  blue, 
indigo,  and  violet.  These  different  colored  rays  are  differently 
refracted  by  the  prism.  The  violet  ray,  as  the  most  refrangible 
one,  is  refracted  towards  V,  and  the  red  one,  as  the  least  re- 
frangible, is  refracted  towards  R,  and  other  colored  rays  fill  out 
the  space  between  Fand  R  in  the  order  of  their  refrangibility. 
This  is  known  as  dispersion.  The  dispersion  of  refracting  me- 
dia is  measured  by  the  length  of  the  spectrum  which  they  pro- 
duce. Flint  glass  has  more  dispersive  power  than  crown  glass, 

because  the  spectrum  which  it  produces  is  longer  than  that  of  crown  glass.  The  dis- 
persion of  a  medium  is  indicated  by  the  difference  of  refraction  between  the  index  of 
refraction  of  the  red  and  the  violet.  Let  us  now  see  what  effect  the  dispersion  has  on 
images  produced  by  single  lenses. 

White  light  a  and  b  is  falling  on  a  double-convex  lens  (Fig.  29).  The  ray  a  is  decom- 
posed into  the  different  colored  rays  as  soon  as  it  enters  the  lens,  and  the  red  ray,  as  the 
least  refracted,  will  cross  the  axis  p  q  in  r,  while  the  violet  ray  crosses  the  axis  in  v. 


FIG.  28. 


FIG.  29. 


FIG.  30. 


A  ^V 6 

Between  the  red  and  violet  the  other  colored  rays  cross  the  axis.    The  same  is  with  the 
ray  b,  and  if  we  do  not  consider  the  spherical  aberration  of  the  rays  between  a  and  b,  all 


52          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

true  image.  To  give  a  rough  illustration,  suppose  the  object  to  be  a  circle. 
The  pencils  from  it  to  the  lens  will  represent  the  surface  of  a  cone.  If  now 
the  transmitted  pencils  are  parallel  with  these,  they  will  form  another  cone, 
whose  section  wherever  cut  by  a  plane  tangentital  to  the  axis  of  the  lens,  must 
be  a  true  circle  like  the  first  or  object. 

the  red  rays  will  have  their  focus  at  r,  and  all  the  violet  ones  at  v.  Between  r  and  v,  the 
foci  of  all  the  other  colored  rays  are  situated.  The  space  between  r  and  v  is  called  the 
longitudinal  chromatic  aberration.  The  length  of  the  aberration  changes  with  the  dis- 
persive power  of  the  media  out  of  which  the  lens  is  made ;  it  is,  for  instance,  twice  as 
great  if  the  lens  is  made  of  flint  glass,  as  if  the  lens  were  made  of  crown  glass.  The 
influence  of  the  chromatic  aberration  on  the  image  of  a  lens  is  shown  in  Fig.  30.  The 
white  light  from  the  object  a  b,  refracted  and  dispersed  by  the  lens  A,  does  not  form  a 
colorless  image,  //',  but  the  red  rays  form  one  at  R  and  R> ',  and  the  violet  at  V  V/.  But 
between  these,  an  endless  number  of  colored  images  of  rays  of  different  refrangibility  are 
produced.  The  red  image  is  the  largest.  If  we  place  a  screen  at  72  R'  we  do  not  get 
simply  a  red  image,  as  all  the  other  dispersed  images  are  formed  on  the  screen  ;  and  as 
the  mixing  of  all  the  different  colors  of  the  solar  light  makes  white  light  again,  so  the 
mixed  images,  that  is,  the  central  part,  is  colorless,  and  only  the  margin  is  blue,  because 
it  is  surrounded  by  the  diffusion  image  of  the  blue  diverging  rays. 

If  the  screen  is  moved  to  V  V,  then  the  image  is  surrounded  by  a  red  margin ;  if  it 
is  moved  to  //',  the  colored  margin  disappears,  but  the  image,  composed  of  the  different 
dispersed  images,  appears  undefined  and  not  clear.  This  effect  is  more  increased, 
because  each  colored  image  has  its  spherical  aberration  also.  Chromatic  aberration 
alone  would  place  the  different  colored  images  in  regular  succession  behind  each  other; 
but  spherical  aberration  mixes  these  images  of  different  colors,  and  only  the  two  outer 
ones,  red  and  violet,  remain.  From  the  foregoing,  it  is  clear  that  chromatic  aberration 
must  necessarily  interfere  with  the  definition  of  a  lens,  and  that  it  is  desirable  to  find  a 
way  to.  correct  this  evil.  From  the  moment  when  Newton  unravelled  the  nature  of  solar 
light,  proving  that  light  is  composed  of  rays  of  different  refrangibility,  our  greatest 
philosophers  and  opticians  have  spent  their  time  and  skill  in  the  attempt  to  produce 
lenses  without  chromatic  aberration,  or  at  least  to  reduce  it  to  a  minimum.  Sir  Isaac 
Newton  was  of  the  opinion  that  refraction  and  dispersion  of  different  refracting  sub- 
stances are  always  in  the  same  ratio  to  each  other,  and  concluded  that  it  was  hopeless  to 
produce  refraction  without  color,  by  combining  convex  and  concave  glasses.  Leonhard 
Euler,  the  great  mathematician,  on  the  other  hand,  reasoned  in  another  way,  and  this 
is  a  curious  instance  of  how  a  correct  conclusion  was  drawn  from  false  premises.  He 
assumed  that  the  human  eye  is  achromatic,  and  consequently  a  lens  could  be  made 
achromatic  too,  and  Newton  must  be  in  error;  he  constructed  theoretical  rules  for 
making  achromatic  lenses,  and  Dollond,  the  optician,  succeeded  in  carrying  them  out. 
But  Dollond,  by  comparing  the  eye  with  his  lenses,  observed  that  the  eye  cannot  be 
achromatic  ;  and  Fraunhofer  afterward  measured  the  chromatic  aberration  of  the  human 
eye,  and  found  that  an  eye  that  is  able  to  bring  parallel  rays  of  red  light  to  focus  on  the 
retina,  can  only  bring  violet  rays  to  a  focus  coming  from  a  distance  of  two  feet. 


ABOUT    LEXSES. 


53 


FIG  31. 


Now  it  will  be  remembered  that  the  especial  property  of  the  optical  centre  in 
lenses  is  this,  that  any  ray  passing  through  it  experiences  no  angular  displace- 
ment, but  has  its  emergent  portion  parallel  with  its  incident  part. 

The  accompanying  cut  illustrates  this  fully — IE,  I'  E',  and  I"  E"  being 
respectively  parallel  to  D  G,  D'  G',  and  D"  G". 

It  would  thus  appear  that  a  common  lens  with  a 
diaphragm,  excluding  all  pencils  but  those  passing 
through  its  optical  centre,  would  fulfil  this  condi- 
tion of  non-distortion. 

Want  of  flatness,  etc.,  however,  practically  ex- 
clude such  an  arrangement,  and  oblige  us  to  resort 
to  compound  lenses. 

The  condition  of  coincidence  in  the  direction  of 
rays  before  and  after  transmission  is  found  in  the 
pin-hole  camera,  of  which  more  anon. 

So  far  for  the  first  condition  of  non-distortion  ; 
but  there  is  yet  another. 

The  pencils  transmitted  must  be  stich  as  would 
have  met,  if  not  refracted,  at  a  common  point. 
The  reason  of  this  is  obvious  after  a  little  reflection. 
If  an  image  were  formed  by  the  action  of  pencils 

which  were  emitted  toward  different  termini,  it  would  suffer  distortion,  like 
that  of  a  perspective  drawing  made  not  from  one  but  from  many  points  of 

Now,  let  us  see  how  we  get  rid  of  these  beautiful  colors,  which  we  admire  so  much  in 
the  rainbow  and  the  glittering  dewdrop,  but  which  hurt  the  eye  of  an  optician  in  an 
optical  instrument.  If  a  ray  of  white  light,  R  (Fig.  32),  falls  obliquely  on  a  parallel 
plane  glass,  it  is  decomposed  as  soon  as  it  enters  the  glass ;  but  on  the  other  side  all 
the  colored  rays  which  made  white  light  are,  on  leaving  the  glass,  parallel  to  their 
former  direction. 


FIG.  32. 


FIG.  33. 


But  if  a  prism,  A  (Fig.  33),  is  struck  by  an  oblique  ray,  R,  the  ray  is  dispersed  in  the 
glass,  and  the  colored  rays  leave  the  prism  diverging,  and  they  cannot  be  properly  mixed 
again  to  white  light,  except  we  can  give  to  the  leaving  rays  their  parallelism  again. 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  34. 


view.  As  an  illustration  we  may  compare  this  action  with  the  effect  of  com- 
bining, to  form  an  image,  part  of  the  picture  of  an  object  seen  with  one  eye, 
with  another  part  as  seen  by  the  other.  Now  a  glance  at  the  cut  will  show  us 
that  the  pencils  which  pass  the  optical  centre  are  not  such  as  would  have  met 
at  a  single  point,  for  while  the  angles  of  the  different  rays  in  the  lens,  with  a 
common  centre,  (7,  are  in  proportion  to  each  other  as  their  arcs,  those  formed 
by  prolongation  of  D  G,  £>"  G,  D"  Gtf  toward  F9  as  refracted  rays,  are  in 
proportion  to  each  other  as  their  sines. 

Now,  if  we  combine  a  prism,  B,  of  the  same  angle  and  material,  in  a  reversed  position 
to  A,  it  is  evident  that  we  restore  the  diverging  rays  again  to  parallel  rays;  but, 
unfortunately,  we  destroy  not  only  the,dispersion,  but  the  refraction — we  make  a  thick, 
parallel  glass  out  of  the  prism. 

Let  us  try  it  in  another  way.  The  ray  E  (Fig.  34),  passes  into  a  prism  of  crown 
glass,  A,  and  a  colored  image  would  be  formed  at  8 t,  if  the  prism  B  would  not  interfere. 
If  we  now  could  combine  with  the  prism  A,  one  of  a  less  angle,  but  made  from  material 
like  flint  glass,  of  greater  dispersive  power,  so  as  to  have  the  same  dispersive  power  as 
the  larger-angle  prism  A,  we  can  restore  the  diverging  into  parallel 
rays,  and  the  light  will  come  out  white  again,  although  it  went 
through  the  compound  prism  CD  E.  This  is  perfectly  practicable, 
if  we  make  the  prism  B  of  flint  glass ;  this  having  a  greater  dis- 
persive power  than  the  crown  glass,  and  the  rays  c  and  d,  when 
entering  the  prism  B,  are  somewhat  refracted — the  violet  more  than 
the  red — and  their  divergency  is  smaller ;  and  if  the  prisms  have  the 
right  proportions,  the  red  and  violet  rays  come  out  into  the  air 
parallel,  and  at  the  same  time,  the  rays  passing  from  the  prism  B 
will  have  a  different  angular  direction  than  that  with  which  they 
entered  the  prism  A.  Thus  we  have  refraction  without  dispersion. 
Let  us  adapt  this  principle  to  a  lens,  A  (Fig.  35),  made  of  crown  glass.  The  rays  a 
and  c  enter  the  lens  at  b  and  d,  and  are  dispersed ;  the  red  would  cross  the  axis  at  r,  and 
the  violet  at  v.  We  associate  the  plano-concave  c,  of  flint  glass,  with  the  lens  A.  As 
the  negative  flint  lens  is  of  a  denser  medium,  the  violet,  as  well  as  the  red  rays,  will  be 
refracted,  but  the  violet  more  so  than  the  red ;  and,  if 
form  and  dispersive  power  of  the  two  lenses  are  in  the 
right  proportions,  the  red,  as  well  as  the  violet,  will 
meet  at  the  point/;  the  image  formed  there  is  colorless, 
or  achromatic,  or,  in  other  words,  it  will  appear  in  its 
natural  colors.  But  even  in  the  best  achromatic  lenses 
there  is  still  a  small  amount  of  color  left,  which  cannot 
be  destroyed.  If  we  compare  the  spectrum  of  a  prism 

of  crown  glass  with  one  of  flint  glass  of  the  same  angle,  we  find  that  the  more  refrangible 
blue,  indigo,  and  violet,  take  not  only  absolutely,  but  also  relatively,  more  space  than 
one  in  the  spectrum  of  the  crown-glass  prism.  So,  if  we  succeed  in  uniting  the  outer 


FIG.  35. 


ABOUT    LENSES. 


55 


It  is  only  for  rays  near  the  axis,  or,  in  other  words,  .for  a  small  angle,  that 
this  second  condition  is  approximately  fulfilled  in  the  case  of  a  single  lens. 

In  the  case  of  the  pin-hole  camera,  however  (diffraction  being  neglected),  this 
condition  is  absolutely  secured. 

If,  now,  we  take  a  combination  of  two  meniscus  lenses,  in  reversed  order  to 
each  other,. and  put  the  stop  in  the  optical  centre  of  the  combination,  we  are 
enabled  to  enlarge  the  angle  very  considerably,  and,  with  a  right  choice  of 
radii,  can  get  the  focus  of  each  pencil  (central  or  marginal)  sufficiently  in  a 
tangent  plane. 

rays,  red  and  violet,  the  intermediate  colors  cannot  unite  completely,  and  this  remainder 
of  uncorrected  colored  rays  we  call  the  secondary  spectrum.  Complete  achromatism, 
therefore,  cannot  be  attained,  but  we  must  be  content  to  come  as  near  as  possible  to  the 
requirements.  A  selection  of  crown  and  flint  glass,  in  which  the  proportions  of  length  of 
the  spectra  of  the  different  rays  are  nearly  related,  will  bring  us  very  near  to  our  purpose. 
Fortunately,  the  colors  of  the  secondary  spectrum  are  feeble,  and  do  not  interfere  much 
with  the  sharpness  of  the  image,  and  we  are  well  pleased  if  a  lens  exhibits  only  the 
secondary  colors — light  purple  and  greenish,  as  it  is  a  proof  that  the  most  objectionable 
effects  from  achromatism  are  removed.  The  association  of  flint  and  crown  glass  serves 
not  only  to  correct  chromatic  aberration,  but,  as  we  have  seen  before,  if  the  right  form 
for  each  of  a  pair  of  lenses  be  selected,  it  corrects  spherical  aberration  also.  Such  a 
lens,  corrected  for  spherical  and  chromatic  aberration,  we  call  an  aplanatic  lens. 

We  now  come  to  another  aberration  of  lenses,  the  curvature  of  field.  The  image  of 
a  flat  object,  formed  by  a  lens,  cannot  be  received  on  a  plane  screen;  the  screen  ought 
to  be  concave.  A,  B,  and  C  (Fig.  36),  are  very  distant  points,  and,  therefore,  nearly 
equally  distant  from  the  lens  Z>,  of  which  the  point  E  is  situated  in  the  line  of  the  axis  of 
the  lens,  while  the  points  A  and  C  are  above  and  below  the  axis.  It  is  evident  that  the 
images  of  these  points  are  formed  at  nearly  equal  distances  from  the  optical  centre,  not 
far  from  the  principal  focus.  »  The  field  F  E  G  is  therefore  curved,  and  cannot  be 
received  on  the  screen  HI  equally  sharp.  The  curvature  of  field  is  generally  attributed 


FIG.  36. 


FIG.  37. 


to  spherical  aberration ;  sometimes  it  is  even  thought  to  be  spherical  aberration  itself, 
but  it  has  nothing  to  do  with  it.  If  lenses  could  be  made  with  parabolic  curves,  free  from 
spherical  aberration,  the  curvature  of  field  would  be  about  the  same. 

Suppose  we  have  a  globular  lens,  A  (Fig.  37),  with  a  diaphragm  in  the  middle,  so 


56 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


As  regards  distortion,  however,  we  cannot  overcome  the  error  .shown  in  the 
case  of  the  single  lens,  but  may  simply  reduce  it.  Perfect  correction  of  distor- 
tion is  just  as  unattainable  as  perfect  correction  of  spherical  or  chromatic 
aberration,  which  last  are  practically  reduced,  not  eliminated,  in  the  best  com- 
binations. All  correction  is,  in  fact,  a  question  not  of  essence,  but  of  degree. 

In  fact,  this  distortion,  as  can  be  readily  proved,  is  but  a  special  case  of 
spherical  aberration,  i.  e.,  for  converging  pencils  or  rays. 

What  can  be  done,  however,  by  proper  arrangement,  the  following  figures 
will  show.  In  one  of  Zentmayer's  lenses,  of  about  twenty-two  inches  focus, 
the  first  radius  is  1.84,  the  second  1.99.  As  Zentmayer  employs  rays  radial 
to  the  first  surface,  the  thickness  of  his  lens  does  not  here  come  in  question. 


FIG.  38a. 


8A  C 


small  as  to  reduce  spherical  aberration  to  almost  nothing.  Now  we  know  that  the  focus 
of  a  sphere  of  crown  glass  is  situated  one-quarter  of  the  diameter  behind  the  globe,  at  B, 
and  as  all  the  pencils  are  normal,  they  all  will  form  their  image  one-quarter  of  the 
diameter  of  the  globe  behind  it ;  that  is,  the  image  lies  in  a  curve,  concentric  with  the 
lens,  although  the  spherical  aberration  is  not  perceptible.  To  understand  the  correction 
of  the  curvature  of  field,  we  must  make  clear  what  is  meant  by  depth  of  focus,  and  what 
the  effect  of  a  diaphragm  is.  Depth  of  focus  is  the  property  of  a  lens  to  give  a  tolerably 
clear  image  of  objects,  not  in  one  plane.  Fig.  38a  and  Fig.  38b 
will  make  it  plain.  In  Fig.  38a  we  make  use  of  the  whole 
aperture  of  a  lens,  D ;  RE  are  parallel  rays,  striking  the 
margin  of  the  lens.  The  image  is  formed  at  a  screen,  A  \  if 
the  screen  is  moved  to  B  or  (7,  the  image  of  the  point  a  spreads 
out,  because  the  angle  of  the  crossing  rays  is  large.  When  the 
same  lens,  D  (Fig.  38b),  is  provided  with  a  diaphragm,  so  as  to 
reduce  the  aperture  considerably,  the  focus  of  the  rays  R  R  is 
still  at  a.  If  we  now  move  the  screen  the  same  distance  as 
before,  to  C  or  D,  we  find  that  the  image  of  the  point  a  is  con- 
l^T  y  siderably  reduced.  If  we  now  look  at  Fig.  36  we  see  that  only 

E  can  be  sharp  on  the  screen,  and  if  the  screen  be  moved  toward 
the  lens  until  the  points  .Fand  O  are  sharply  defined  upon  it, 
then  the  point  E  will  lie  beyond  the  screen  and  become  indis- 


BAG 


FIG.  38b. 

tinct;  but  if  we  provide  the  lens  with  a  small  central  diaphragm,  we  can  find  a  place  for 
the  screen  where  all  three  points  can  be  brought  to  it,  without  the  images  being  sensibly 
diminished  in  sharpness. 

Now  let  us  see  what  takes  place,  if  we  move  the  diaphragm  to  a  proper  distance  from 
the  lens.  A  B  C  (Fig.  39)  are  distant  points,  L  a  converging  lens.  Let  us  trace  the 
course  of  the  rays,  commencing  from  tjie  points  A,  B,  C.  The  rays  from  the  points  B, 
situated  in  the  axis,  and  the  image  of  the  point  B  will  be  formed  at  F,  the  principal 
focus.  But  it  is  different  with  the  rays  coming  from  A  and  C.  The  rays  proceeding 
from  the  point  A — A1,  A",  AM,  Aiv,  A",  are  refracted  to  a,  b,  c,  d,  e;  similarly  the  rays 


ABOUT    LENSES. 


57 


A  radial  ray  5°  from  the  centre  will  cross  the  axis  at  a  distance  of  1.719 
inches  from  the  first  surface ;  a  radial  ray  of  20°  at  1.72  inches ;  and  a  ray  36° 
at  1.724 ;  giving  a  difference  between  rays  of  5°  and  36°  of  but  0.005  (-n^)  of 
an  inch,  with  a  focal  length  of  twenty-two  inches. 

To  produce  a  lens  of  least  distortion  it  is  not  only  necessary  therefore  that 
some  ratio  should  exist  between  the  components  of  the  system,  but  a  certain 
and  exact  relation  must  be  established,  which,  once  fixed,  will  apply  to  all 
cases,  and  by  reason  of  which  each  transmitted  pencil  from  any  part  of  the 
front  lens  will  find  just  an  equivalent  part  of  the  second  lens  to  correct  its  dis- 
tortion. In  the  Globe  lens  (a  special  instance  of  this  principle)  such  a  result 
is  obtained  in  one  case ;  that  is,  when  it  is  used  to  copy  full  size,  so  that  object 
and  image  have  equal  dimensions. 

from  the  point  C  are  refracted  to  a',  b'}  c' ',  d',  e/ ;  occasioning,  as  we  have  seen  before, 
spherical  aberration.  If  we  place  a  screen  at  the  principal  focus  F,  it  will  not  receive  a 
distinct  image,  even  if  we  have  a  concave  screen ;  as  will  be  observed,  all  the  rays  outside 
of  the  axis  arrive  at  different  distances  behind  the  lens.  You  notice  that  none  but  the 


FIG.  39. 


FIG.  40. 


rays  Aiv  and  Av,  <74  and  (75,  have  their  foci  near  the  plane  of  the  screen  M  N.  Now  if 
we  find  a  place  for  a  diaphragm,  so  that  only  these  rays  pass  the  lens,  and  the  depth  of 
the  lens  is  as  great  as  d  M,  we  may  expect  a  pretty  sharp  image  on  a  plane  screen.  By 
looking  over  the  figure,  we  see  that  such  a  plane  is  in  OP  (Figs.  39  and  40).  A 
diaphragm  in  this  place,  and  of  the  proper  size,  will  allow  only  the  most  favorable  rays 
to  pass,  and  a  tolerably  flat  and  sharp  image  is  obtained.  The  smaller  the  diaphragm 
the  sharper  and  flatter  the  image.  But  as  we  mentioned  before,  small  diaphragms  have 
the  disadvantage  that  the  light  is  cut  off  to  such  an  extent ;  and  for  most  purposes  the 
lens  becomes  useless.  But  suppose  we  would  employ  a  negative  lens,  under  the  same 
conditions,  we  would  have  no  real  image,  but  a  virtual  one,  the  curvature  of  the  field 
would  be  reversed,  and  the  marginal  rays  have  a  longer  focus  than  the  central  ones. 


58 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


So,  again,  Mr.  Zentmayer  has  developed  a  certain  ratio,  which,  once  estab- 
lished, remains  the  same  throughout  all  his  combinations ;  and  the  same  will 
be  shown  by  an  intelligent  study  of  all  other  effective  arrangements  which  have 
in  view  the  same  object  of  securing  minimum  distortion. 

Lack  of  depth,  and  its  attendant  inconveniences,  have  hitherto  been  a  great 
drawback  to  artistic  freedom  of  effect  in  photographic  portraiture. 

In  arranging  a  model  for  the  simplest  form  of  picture,  a  bust,  how  disagree- 
able the  effect  of  the  blurred  outline  of  the  further  shoulder. 

The  impossibility  of  obtaining  equal  distinctness  at  unequal  distances  from 
the  instrument,  more  than  all  other  causes  put  together,  make  photographs  stiff, 
formal,  heartless,  and  produces  those  conventional  peculiarities  in  sun-pictures, 

Therefore,  it  is  possible  to  associate  a  negative  with  a  positive  lens  and  to  render  the 
field  flat. 

The  next  aberration  which  we  have  to  deal  with  is  the  distortion.  If  we  describe  a 
network  of  straight  lines  (Fig.  41),  and  hold  a  convex  lens  over  it,  placing  the  eye  at  a 

distance  from  it  in  the  axis  of  the  lens, 
only  the  two  right-angle  lines  of  the 
centre  appear  straight ;  the  others  appear 
curved.  When  the  upper  is  in  the  re- 
verse position  to  the  lower  one,  they 
appear  pincushion-shaped.  Distortion 
of  the  negative  lens  is  reversed ;  the  lines 
appear  as  the  curved  sides  of  a  barrel. 
The  cause  of  distortion  is  somewhat  difficult  to  explain,  but  the  following  figures  make 
it  clear.  Let  us  describe  upon  a  plate  or  plane  surface  a  number  of  circles,  A,  B,  C, 
equidistant  from  each  other  (Fig.  42  in  front  view,  and  Fig.  43  in  profile),  and  place  in 
front  of  them  (Fig.  43)  the  lens  L.  Now  the  rays  which  proceed  from  A,  B,  C,  parallel 
to  the  axis  of  the  lens,  strike  it  at  d,  e,  g,  from  whence  they  will  be  refracted,  and  meet 

FIG.  42. 


FIG.  41. 


at/,  the  principal  focus.  If  we  place  the  eye  at/,  we  see  the  circle  A,  not  where  it  really 
is,  but  in  the  direction  /  d,  the  circle  B  in  the  direction  /,  e,  and  the  circle  C  in  the 
direction  /  g.  By  prolonging  the  lines  of  direction  until  they  meet  the  plane  of  the 


ABOUT    LENSES. 


59 


which  rendered  a  photograph  of  any  kind,  from  life,  or  its  engraved  reproduc- 
tion, recognizable  as  far  as  it  is  visible. 

How  it  was  to  be  removed,  or  at  least  so  far  removed  as  to  give  us  practi- 
cally the  necessary  freedom,  was  a  puzzle. 

A  theoretical  answer  would  be,  "  by  constructing  a  lens  which  shall  have 
equal  foci  for  objects  at  different  .distances  from  itself."  But  theory  again  says, 

circles  A,  JB,  C,  we  observe  that  the  circles  do  not  appear  equally  apart,  but  their  distance 
is  increasing  from  C  to  A ;  they  will  appear  as  in  Fig.  44. 

We  will  suppose  for  a  moment  that  the  circles  A  and  B  (Fig.  42)  are  of  such  relative 
diameters  that  a  square  inclosing  B,  with  its  sides  tangenital,  shall  have  its  corners  in 
the  circle  A.  Now  if  we  draw  the  circle  A  and  B  (Fig.  44),  (as  they  will  appear  from 
/),  the  distance  between  A  and  B  will  be  greater,  or  equal  to  a  b  (Fig.  43),  and  as  the 
contact  of  the  side  of  the  square  with  B  (tangentially)  and  with  A  at  the  ends  must  be 
kept,  the  line  of  the  side  will  now  appear  curved  or  bent  (Fig.  44). 


FIG.  44. 


FIG.  45. 


FIG.  46. 


A  single  lens  without  distortion  cannot  be  made,  but  by  combining  two  or  more  lenses 
in  connection  with  diaphragms  in  a  certain  position  the  distortion  can  be  corrected  com- 
pletely. If  a  diaphragm  is  placed  in  front  of  a  lens  L  (Fig.  45),  different  parts  of  the 
lens  are  employed  to  form  different  parts  of  the  object  CD.  In  this  case  the  distortion 
is  barrel-shaped ;  but  by  placing  the  diaphragm  behind  the  lens  (as  in  Fig.  46)  the  dis- 
tortion is  of  the  opposite  nature — that  is,  pincushion-shaped.  Rays  coming  from  D  (Fig. 
45)  pass  through  the  upper  part  of  the  lens,  while  in  the  latter,  through  the  lower  part. 

Now  you  will  readily  see  that,  by  uniting  two  lenses  equal  to  each  other,  L,  L' ,  (Fig. 
47),  and  placing  a  diaphragm,  D,  between  them,  it  follows  that  the  distortion  accom- 
panying  the  lens  L,  with  its  diaphragm  behind  it,  is  cor- 
rected by  the  action  of  the  same  diaphragm,  upon  the  rays 
entering  the  lens  L',  where  the  diaphragm  is  now  in  front  of 
the  lens  // '.  The  modern  photographic  objectives  to  be  used 
for  architectural  work  and  copying  are  constructed  on  this 
principle. 

Unfortunately  this  advantage  is  obtained  at  the  sacrifice 
of  aperture,  that  is,  of  light.     I  mentioned  before  that  the 
negative  lens  has  the  opposite  distortion  of  the  positive  lens, 
so  that  by  proper  combination  of  lenses  of  suitable  curves  any  material  distortion  can 
nearly  be  overcome  upon  a  limited  field. 


FIG.  47 


B 


60 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


"this  is  impossible."  Just  here,  however,  is  noticed  a  divergence  between 
theory  and  practice,  or,  to  speak  more  correctly,  we  see  that  some  theories 
cannot  be  perfectly  carried  into  practice  (and  that  there  might  not  accrue  much 
advantage  if  they  could  be). 

It  was  left  for  M.  Claudet  to  give  an  ingenious  plan  by  which  the  two  com- 
binations of  the  ordinary  portrait  tube  being  gradually  made  to  approach  each 
other  during  exposure,  the  plane  of  greatest  sharpness  moves  through  the  whole 
subject,  resting  alternately  on  each 'part  from  Trout  to  rear,  thus  diffusing  the 
focus  evenly  over  the  sitter. 

This  method  requires  very  heavy,  firm  stands,  steady  nerves,  and  nice  judg- 
ment in  the  operator.  It  was  asserted  that  M.  Claudet  produced  some  exquisite 
results. 

Mr.  J.  H.  Dallmeyer  invented  a  lens  capable  of  giving  any  amount  of 
diffusion,  with  its  concomitant  depth,  that  may  be  required. 

Photographic  objectives  used  for  portrait  purposes,  when  a  large  quantity  of  light  is 
desirable  for  brief  exposure,  are  thus  corrected ;  but  these  are  again  open  to  the  fault  of 
a  restricted  angle  of  vision.  In  all  other  lenses,  when  the  light  is  the  desirable  element 
to  be  preserved,  the  correction  of  distortion  must  be  made,  as  far  as  possible,  by  a  com- 
bination of  lenses. 

We  now  come  to  the  last  of  the  more  important  aberrations,  that  is  the  astigmation, 
a  word  coming  from  the  trreek,  meaning,  not  coming  to  one  point.  If  we  focus  a  well- 
defined  round  object,  situated  in  the  axis  of  a  lens  of  a  wide  aperture,  on  a  screen,  we 
find  the  image  round ;  even  if  we  move  the  screen  in  and  out  of  the  focus,  the  image  will 
get  only  less  sharp ;  but  if  we  turn  the  lens  sideways,  so  as  to  get  the  image  of  the  same 
object  formed  by  pencils  oblique  to  the  axis,  then  we  will  observe  that  it  is  no  longer 
possible  to  form  a  sharp  image  of  the  object,  and  by  moving  the  screen  in  and  out  of  the 
focus  the  image  appears  elongated,  horizontally  or  vertically. 

Now  let  us  see  whether  it  can  be  made  clear  in  the  following  figure  (48).     CD  is  a 
convex  lens,  of  which  A  B  is  the  axis.     The  lens  is  represented  in  perspective,  as  we 
have  to  show  two  planes,  in  different  directions.     The 
radiating  point  R  is  situated  at  infinity,  and  outside  of 
the  principal  axis.     We  will  lay  a  plane  through  the 
axis  A  B  and  the  point  R,  which  will  cut  the  lens  in  its 
diameter  CD.     Let  us  lay  another  plane  through  the 
point  R,  at  a  right  angle  to  the  former,  and  which  will 
cut  the  lens  in  its  diameter  E  F.     If  we  draw  the  line 
Rp  through  the  optical  centre  of  the  lens,  a  ray  following 
it  would  not  be  refracted,  as  we  have  seen  before,  and 
constitutes  a  secondary  axis.    R p  is  the  line  where  the 
two  planes  cut  each  other,  and  consequently  belongs  to 
both  planes.     Let  us  draw  the  two  extreme  rays,  R'  C and  R'  D  of  the  diameter  CD, 
which,  after  refraction  are  T'and  p',  as  we  learned  by  analyzing  spherical  aberration.    If 


FIG.  48. 


ABOUT    LENSES.  >  61 

The  back  combination  varies  from  the  old  style  in  its  curves,  and  trie  iwo 
lenses  that  compose  it  are  mounted  so  that  they  can  be  brought  near  together 
or  set  apart,  by  turning  a  screw.  When  close  together,  they  produce  pictures 
on  the  old  plan  of  one  plane  of  sharpness ;  by  separating  them,  the  sharpness 
is  lessened,  and  the  focus  diffused  so  that  a  series  of  objects  situated  between 
fifteen  and  eighteen  feet  from  the  camera  can  all  be  rendered  equally  we.i,  with 
the  full  aperture  and  field  of  the  lens. 

Some  of  these  instruments  are  in  use,  but  the  "  diffusion "  principle  is  not 
much  practised.  Great  improvements  have  been  made  in  lei^es  for  large 
figures,  and  the  modern  dry  plate  enables  the  photographer  to  employ  lenses  of 
longer  focus  which  were  considered  "absolutely  too  slow"  a  few  years  ago. 

Large  direct  portraits,  therefore,  are  now  more  the  rule  than  the  exception. 

we  now  look  to  the  other  plane,  the  rays  R"  jPand  R"  E  are  symmetrical  to  the  axis, 
and  are  exactly  equally  refracted,  meeting  at  the  point  S.  If  the  lens  is  now  diaphragmed 
down,  so  as  to  improve  the  aberration  of  the  plane  CD,  we  find  that  we  have  for  one 
lens  two  distinct- foci.  If  we  focus,  for  instance,  a  brick  wall,  we  will  have  the  horizontal 
white  mortar  lines  in  focus,  while  the  vertical  ones  are  out  of  focus,  and  vice  versa.  By 
looking  to  the  figure  you  can  easily  see  that  that  universal  doctor  in  optics,  the  dia- 
phragm, will  also  cure  astigmation,  at  least  will  bring  it  to  a  minimum.  Fig.  47  will 
suggest  a  way  by  which  astigmation  may  be  destroyed  almost  completely.  The  diaphragm 
D  divides  the  lens  L  into  an  infinite  number  of  lenses,  of  which  each  acts  on  a  different 
radiating  point,  and  the  pencils  in  or  out  of  the  axis  strike  the  lenses  almost  normal, 
hence  such  a  combination  is  not  only  nearly  free  of  distortion,  but  of  astigmation  also. 

In  nearly  all  human  eyes  there  exists  an  aberration,  also  called  astigmation.  Although 
in  its  effect  similar  to  the  astigmation  of  lenses,  just  mentioned,  it  is  of  a  different  char- 
acter. Nature  intends  that  the  curves  of  the  cornea  and  crystalline  lens  of  the  human 
eye  should  be  spherical;  but  the  exceptions  seem  to  be  the  rule.  The  curves  of  the 
cornea  and  crystalline  lens  of  the  eye  are  in  nearly  all  cases  more  or  less  elliptical,  egg- 
shaped,  and  consequently  have  in  one  meridian  a  longer  focus  than  in  the  other.  If  such  an 
eye  brings  the  image  of  a  line  parallel  to  one  meridian  to  a  focus  at  the  retina,  the  images 
of  lines  parallel  to  all  the  other  meridians  do  not  collect  at  the  retina,  especially  the  one 
at  right  angles  to  the  former,  and  a  distorted,  blurred  image  is  the  result.  The  advance- 
ment of  science  has  lately  enabled  our  oculists  to  correct  this  evil  by  spectacles,  of  which 
the  glasses  are  parts  of  cylinders  instead  of  spheres. 

Now,  knowing  all  the  defects  of  lenses,  and  the  different  modes  of  correcting  the  same, 
let  us  look  back  to  that  primitive  instrument — the  pinhole  camera.  The  pinhole  camera 
is  free  from  all  the  errors,  as  spherical  and  chromatic  aberrations,  distortion,  curvature 
of  field,  astigmation,  and  the  only  objection  against  it  is  the  extremely  small  aperture. 
What  an  amount  of  speculation  and  hard  labor  of  the  most  eminent  men  were  necessary 
to  furnish  a  substitute,  equally  free  from  errors,  having  a  larger  aperture,  giving  a  brighter 
image.  And,  even  now,  none  of  the  aberrations  can  be  completely  corrected,  and  the 


62          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Enough  has  been  said  to  aid  the  buyer  in  his  selection,  though  the  following 
points  are  essential : 

Avoid  any  brownness  of  color,  detected  by  placing  the  lens  on  a  sheet  of 
white  paper. 

Bubbles  of  any  size  often  impair  the  brilliancy  of  the  image. 

Scratches  and  hairlines  should  cause  a  lens  to  be  rejected. 

Centring. — To  every  lens  there  belongs  an  optical  axis,  a  line  perpendicular 
to  the  surface  of  the  lens,  and  passing  through  its  centre  of  curvature.  Every 
achromatized  lens  consists  of  at  least  two  portions,  and  it  is  necessary  that  these 
should  be  so  arranged  when  attached  together  by  the  balsam  used  for  that 
purpose,  that  the  optical  axis  of  each  should  exactly  correspond.  When  two 
lenses  or  more  are  united  to  form  an  objective,  not  only  must  the  parts  of  each 
be  properly  disposed,  but  the  front  lens  must  have  its  axis  coincident  with  that 
of  the  back  lens.  This  will  depend  upon  correct  mounting. 

To  make  the  test,  the  observer  places  himself  in  a  dark  room  with  a  single 
candle.  Standing  five  or  six  feet  from  it,  he  looks  at  it  through  the  objective, 
inclining  the  latter  a  little  until  he  sees  a  series  of  bright  points,  which  are  the 
images  of  the  candle,  produced  by  successive  reflections  from  the  different  sur- 

best  that  can  be  done,  and  that  for  a  limited  aperture  only,  is  to  reduce  the  errors  so  far 
as  to  diminish  their  extension,  so  as  to  make  them  appear  to  our  eye  at  a  smaller  angle 
than  the  eye  is  able  to  distinguish.  In  lenses  used  as  objectives,  where  the  image  is 
magnified  by  high  eye-pieces,  even  that  is  extremely  difficult,  as  the  errors  are  also  mag- 
nified. Our  most  celebrated  opticians,  such  as  Fraunhofer,  never  attempted  to  give  a 
telescopic  objective  a  larger  aperture  than  the  focus  divided  by  ten,  except  in  very  small 
pocket  telescopes.  And  his  larger  telescope,  the  one  he  made  for  the  Dorpat  Observatory, 
and  which  he  considered  his  best  objective,  has  a  focus  of  160  inches,  while  the  aperture 
is  only  108  lines,  that  is  ^7th  of  the  focal  length,  and  its  highest  magnification  is  720  times. 
The  larger  telescopes  of  Dollond  are  nearly  twice  as  long.  The  same  artist,  Fraunhofer, 
took  precaution  to  warn  young  opticians  and  amateurs  not  to  listen  to  the  very  natural 
desire  to  try  their  skill  on  larger  apertures,  and  giving  higher  magnification,  if  they  do 
not  wish  to  be  disappointed,  and  lose  time  and  money.  But  the  school  of  experience 
seems  to  be  the  only  one  to  cure  this  desire. 

But  here  I  feel  bound  to  mention  that,  a  few  years  ago,  Mr.  Steinheil,  of  Munich,  read 
a  paper  before  the  Academy  of  Sciences  of  that  city,  on  an  improved  telescope  objective. 
It  is  composed  of  four  lenses— one  positive  crown-glass  lens,  combined  with  a  compound 
negative  lens,  which  itself  is  a  triplet  of  two  flint  and  one  crown-glass  lenses.  By  this 
formula  a  four-inch  telescope  is  only  two  feet  long,  while  in  the  ordinary  way  it  is  twice 
as  long. 

While  I  am  speaking  about  wide  apertures,  I  cannot  pass  without  mentioning  a  very 
serious  obstacle  connected  with  large  apertures;  it  might  be  called  the  parallactic  error. 


ABOUT    LENSES..  63 

faces  of  the  lens.  When  a  lens  has  four  pieces  of  glass  in  its  construction,  as 
in  the  case  of  the  portrait,  globe,  orthoscopic,  and  some  other  lenses,  the  number 
of  possible  images  is  very  considerable.  These  cannot  generally  be  all  found 
at  once,  but  eight,  ten,  or  more  can  be  counted ;  a  little  practice,  and  altering 
the  inclination  of  the  lens,  materially  aids  in  increasing  the  number. 

If  now  the  centring  is  perfect,  it  will  be  found  that,  by  carefully  adjusting 
the  position  of  the  lens,  all  of  these  reflections  can  be  made  to  range  themselves 
in  a  straight  line.  But  if  any  one  or  more  of  the  component  parts  is  out  of 
centre,  this  will  be  found  impracticable.  One  or  more  of  the  bright  points  will 
remain  obstinately  out  of  line ;  and,  wThen  a  little  movement  is  made  which 
brings  them  in,  it  will  be  found  that  some  other  image,  previously  in  line,  has 
slid  out  of  it.  When  the  observer,  after  very  careful  trial,  finds  that  it  is 
positively  impossible  to  make  all  the  images  range,  he  will  be  justified  in  con- 
cluding that  there  is  a  fault  in  the  centring. 

Chemical  Focus. — The  correction  for  chromatic  aberration  is  now  greatly 
better  made  than  formerly.  To  test  whether  a  lens  is  properly  corrected, 
select  a  newspaper  printed  with  sharp-cut  type,  and  paste  a  piece  a  foot  or 
fifteen  inches  square  upon  a  smooth  piece  of  board.  Set  this  up  before  the 
camera,  with  the  columns  vertical,  but  inclined  in  a  slanting  direction,  so  that 
one  side,  the  right,  for  example,  shall  be  a  couple  of  inches  nearer  the  camera 

I  am  frequently  asked  why  a  large  photographic  object  does  not  give  the  same  sharp 
image  that  a  small  one  does.  It  is  somewhat  more  difficult  to  correct  a  large  objective 
than  a  small  one,  even  if  the  aperture  stands  in  the  same  relation  to  the  focal  length. 
But  it  is  not  only  this.  Suppose  we  have  a  large  photographic  objective,  say  of  six  inches 
aperture,  L  (Fig.  49).  Each  part  of  the  lens  receives  radiating  rays  from  each  point  of 
the  object,  and  brings  them  to  a  focus,  the  respective  place.  Now 
if  we  cover  the  lens  by  pasting  paper  over  it,  leaving  only  the  aperture  FIG.  49. 

A  free,  we  still  get  an  image,  only  more  feeble  in  light.  Again,  cover 
the  aperture  A,  and  open  the  aperture  B,  you  get  an  image  of  the 
same  object;  but  the  apertures  A  and  B  are,  say,  four  inches  apart. 
Both  cannot  give  precisely  the  same  image,  as  they  are  taken  from 
another  base.  The  images  will  be  similar  to  the  two  images  of  a 
stereograph,  which  are  taken  in  &  similar  way  by  two  lenses.  Now 
open  both  apertures,  A  and  B,  and,  as  the  images  are  not  equal,  they 
cannot  cover  each  other,  but  will  overlap,  especially  the  images  of  the  nearer  objects. 
If  we  now  use  the  whole  aperture  of  six  inches  diameter,  it  is  clear  that  we  will  have  an 
infinite  number  of  images  none  equal  to  the  other,  every  one  overlapping  the  other,  and 
the  image  necessarily  must  be  a  blurred  one.  For  this  there  is  no  remedy  but  cutting 
down  the  aperture. 
We  now  have  a  reasonable  knowledge  of  what  a  lens  is. — JOSEPH  ZENTMAYER. 


64          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

than  the  left,  keeping  the  board,  however,  exactly  upright.  Focus  carefully 
along  the  central  upright  line,  and  copy  it  full  size,  or  thereabouts. 

Next  examine  the  hair-strokes  of  the  letters  on  the  negative  with  a  micro- 
scope. If  the  lens  is  properly  corrected,  the  central  line  should  be  in  the 
sharpest  focus.  If,  however,  it  be  found  that  a  portion  to  the  right  or  left  of 
the  central  line  is  in  better  focus  than  the  centre,  then  the  correction  has 
evidently  been  faulty.  If  the  sharpest  image  is  of  a  part  nearer  to  the  lens 
than  the  centre,  the  lens  is  under-corrected;  if  of  a  part  further  from  the  centre, 
the  lens  is  over-corrected.  In  either  case,  it  is  said  to  have  a  chemical  focus — 
that  is,  its  chemical  and  visual  focus  do  not  correspond,  a  fault  of  the  first 
magnitude,  and  sufficient  cause  for  rejecting  the  lens  entirely. 

And  yet,  after  all  these  tests,  our  nearly  perfect  instrument  needs  a  great 
deal  of  intelligent  "managing"  under  the  skylight  before  it  can  be  made  to 
produce  its  best  results. 

This  part  of  the  subject  is  so  important,  that  the  next  chapter  will  be 
devoted  to  the  managing  machinery,  namely,  to  the  "stop"  or  "diaphragm." 

15.  A  word  as  to  the  care  of  lenses.  Only  the  softest  fabrics  or  chamois  skin  should 
be  used  to  wipe  them ;  they  should  not  be  fingered.  Keep  your  head  clear  when  you 
separate  their  parts,  that  you  may  replace  them  exactly.  Then  be  careful  not  to  expect 
one  lens  to  do  everything.  For  varied  work  there  must  be  a  variety  of  lenses. — GEORGE 
W.  WALLACE. 


CHAPTER   VI. 


Terrain 


THE   DIAPHRAGM  OR   STOP. 

16.  THE  original  purpose  of  the  diaphragm  was  to  "stop"  the  passage  of 
certain  useless  rays  through  the  lens,  thus  preventing  the  distortion  which 
would  follow  their  admission,  and  by  so  doing  secure  a  more  correct  and  sharp 
image. 

16.  The  first  thing  to  do  is  to  understand  thoroughly  the  march  of  the  luminous  rays. 
The  pure  and  simple  analysis  of  the  phenomena  produced  will  always  furnish  us  some 
useful  information. 

Let  us  take  as  a  type  a  rectilinear  objective,  the  use  of  which  is  very  frequent  in 
instantaneous  photography.  The  reasoning  may  also  be  applied  to  the«imple  objective. 

Suppose  A  B  to  be  the   object 

that  we  wish  to  reproduce.    The  ^IG.  50. 

point  A  sends  a  pencil  of  light  on 
the  first  lens;  slightly  deviating, 
these  rays  strike  in  a  parallel  man- 
ner the  second  lens,  on  which  they 
are  again  refracted  and  form  at  A/ 
the  image  of  A.  The  point  B  acts 
in  the  same  manner  and  gives  an 
image  at  B'.  All  the  points  of  the 
line  A  B  give  a  similar  image  be- 
tween A/  B' .  It  is  seen  at  once  that  the  image  is  reversed.  In  our  cut,  A  represents 
the  sky  and  B  the  earth.  On  the  ground-glass  the  earth,  B',  is  above  and  the  sky,  A' 
below.  From  this  first  remark  we  shall  already  be  able  to  draw  some  interesting  con- 
clusions. If,  placing  a  plate  pierced  with  an  opening  before  the  objective,  we  cause  it  to 
descend  slowly,  we  see  that  it  will  allow  rays  emanating  from  A  to  pass  first,  then  suc- 
cessively the  intermediate  ones  from  A  to  B,  and,  finally,  those  coming  from  B.  In  con- 
tinuing the  movement,  it  is  the  rays  emanating  from  A  which  disappear  first  and  those 
at  B  last.  On  our  ground-glass  the  sky  commences  to  appear,  then  the  landscape,  and 
finally  the  foreground ;  at  this  time  the  image  is  complete,  then  the  reverse  is  produced, 
the  last  planes  being  the  last  visible.  If  the  plate  has  a  uniform  motion  the  lighting  of 
the  different  portions,  although  not  having  been  made  strictly  at  the  same  time,  will  be 
equal  as  regards  the  duration.  If,  on  the  contrary,  the  movement  is  accelerated,  either 
by  a  free  fall  or  by  the  action  of  a  spring,  the  image  will  be  unequally  lighted.  In*  the 
present  case,  it  is  the  ground  which  will  receive  the  shortest  exposure.  This  result  is 
contrary  to  the  facts  shown  by  photography,  which  require  a  longer  exposure  for  the 

5  (65) 


Terrain 


66 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


Diaphragms  are  of  various  shapes.  Some  are  mere  disks,  or  strips  of  metal 
perforated  in  the  centre  and  made  to  enter  through  a  slit  in  the  lens  tube. 
Others  are  disks  of  metal  supplied  with  holes  of  various  sizes,  and  so  contrived 

first  planes  than  for  the  sky.  We  therefore  think,  in  a  theoretical  point  of  view,  that  the 
use  of  the  shutter  in  front  of  the  objective  is  defective.  And  if  in  going  backward  we 
make  the  same  reasoning,  we  will  find  that  the  results  are  reversed.  The  sky  will  have 
the  shortest  exposure  and  the  ground  the  longest.  This  solution  seems  to  us  preferable 
in  every  way.  The  drop  used  for  this  demonstration  is  the  one  styled  the  guillotine.  We 
may,  therefore,  admit  in  principle  that  there  is  every  advantage  in  placing  the  guillotine 
behind  the  objective,  in  preference  to  before  it.  Some  had  proposed  to  place  the  guillo- 
tine in  the  objective  at  the  optical  centre,  or  rather  at  a  very  near  plane,  so  as  not  to 
prevent  the  use  of  the  stops.  This  position  seems  at  first  to  be  very  advantageous,  since 
as  soon  as  the  guillotine  acts  it  should  unmask  equal  quantities  of  rays  coming  from  A 
and  from  B.  From  the  start,  the  image,  therefore,  would  be  entirely  visible  on  the 
ground-glass.  As  the  guillotine  continues  its  movement  the  sum  of  the  rays  admitted 
would  increase  in  the  same  proportions  for  the  points  A  and  B.  The  image  would 
become  more  and  more  bright,  to  disappear  in  the  same  way  by  general  extinction.  The 
image  would,  therefore,  be  complete  during  the  whole  time  of  exposure.  A  thorough 
investigation  of  the  question  has  proved  to  us  that  the  image  is  not  produced  in  this 
manner.  In  order  to  analyze  the  formation  of  images  M.  Darlot  has  constructed  for  us 
an  objective  which  allows  the  working  of  metallic  plates  pierced  with  openings  in  five 
different  positions :  before  and  behind  the  lenses,  at  the  optical  centre,  before  and  behind 
this  last.  Placing  the  plate  back  of  the  optical  centre,  he  saw  that  the  image  was  not 
complete  from  the  start.  It  appears  little  by  little,  near  the  centre  of  the  glass  plate, 
like  a  spindle,  analogous  in  shape  to  that  of  the  segment  uncovered  by  the  diaphragm. 
Fig.  51  shows  the  appearance  of  the  image  on  the  ground-glass  according  to  the 
position  of  the  stop.  A,  stop  placed  before  the  objective;  B,  stop  placed  near  the  centre 

of  the  objective;  C,  stop  placed  back  of 
the  objective.  When  this  continues  its 
motion,  the  image  becomes  enlarged  on 
both  sides  like  a  double  folding-door. 
The  action  of  the  stop  is  the  same,  one 
portion  of  the  plate  shaped  like  a  spindle 
being  the  last  to  remain  lighted,  but  in 
a  position  like  that  of  the  first  spindle  as 
regards  the  centre  of  the  plate.  If  a 
diaphragm,  however  small  it  may  be, 
placed  in  the  axis  of  the  objective, 
always  gives  a  complete  image,  a  dia- 
phragm not  in  the  centre  as  regards  this  axis  does  not  give  the  same  result.  In  this  case, 
some  rays  only  can  pass,  those  coming  from  the  centre  of  the  image;  the  others  are  inter- 
cepted by  the  sun-screen,  or  are  lost  in  the  interior  of  the  mounting.  The  rather  abstruse 
explanation  of  this  phenomenon  would  carry  us  too  far. 


FIG.  61. 


THE    DIAPHRAGM    OR    STOP.  67 

as  to  revolve  and  bring  one  of  these  holes  over  the  focal  centre  of  the  lens  at 
each  movement.  The  importance  of  the  diaphragm  is  very  great.  Too  much 
attention  cannot  be  given  to  its  application  in  practice. 

To  resume,  if  we  wish  to  represent  the  manner  in  which  the  image  would  appear, 
according  to  the  divers  positions  of  the  diaphragm  in  the  objective,  we  will  have  the 
following  representation  (Fig.  51) :  In  front,  the  sky  appears  first ;  back,  it  is  the  ground. 
At  the  optical  centre,  or  near  it,  we  find  the  almost  central  portion  of  the  image.  It 
seems,  therefore,  that  the  passage  of  a  stop,  uncovering  the  objective  laterally,  should  be 
absolutely  condemned  in  a  theoretical  point  of  view,  since  in  the  first  cases  the  image 
is  successive  and  in  the  others  it  is  always  unequal.  Struck  with  the  objections  which 
are  presented  by  the  theory  of  stops  which  uncover  the  objective  laterally,  and  on  the 
other  hand  remarking  that  the  prints  obtained  with  these  appliances  contain  none  of  the 
defects  that  theory  seemed  to  indicate,  we  have  endeavored  to  discover  from  what  arose 
this  difference  between  the  theoretical  and  practical  results.  We  ascertained  that  the 
action  of  these  stops  is  not  the  same  when  the  velocity  is  moderated  experimentally,  to 
control  the  manner  in  which  the  image  is  produced,  or  when  the  appliance  works  at  its 
normal  degree  of  velocity.  An  image  that  appears  unequally  lighted  or  having  aberra- 
tions when  the  appliance  works  slowly,  does  not  appear  when  it  works  rapidly.  Our 
eye  perceives  it  when  the  appliance  is  retarded  in  its  movement ;  but  as  soon  as  the 
rapidity  becomes  great,  the  intensity  is  not  sufficient  to  act  on  the  sensitive  surface.  The 
light  that  penetrates  into  the  appliance  when  the  shutter  works,  presents  an  increasing 
intensity  from  obscurity  until  complete  illumination,  intensity  depending  upon  the 
number  of  rays  progressively  admitted.  It  is  only  when  the  intensity  is  sufficient  that 
the  impression  commences.  This  is  a  fact  easy  to  verify  by  all  the  optical  methods  of 
photographic  registry. — ALBERT  LONDE. 

There  is  no  step  in  photography  that,  could  be  accomplished  with  so  much  facility  in 
proportion  to  its  importance  as  the  one  connected  with  stops. 

If  all  makers,  instead  of  stamping  numbers  or  other  marks  upon  their  diaphragms, 
would  stamp  opposite  to  each  opening  the  relation  of  its  diameter  to  the  focal  length  of 
the  lens,  the  advantage  would  be  exceedingly  great.  The  openings  would  then  be 
marked  /20,  /25,  etc.,  or,  omitting  the  /  as  being  understood,  simply  20,  25,  30,  etc., 
indicating  that  the  opening  in  question  was  one-twentieth,  one-twenty-fifth,  etc.,  the 
focal  length  of  the  lens  or  combination.  The  following  benefits  would  result^from  this 
change : 

The  photographer  who  uses  a  number  of  lenses,  in  place  of  being  obliged  to  remember 
the  relations  of  each  diaphragm  of  each  lens  to  light,  so  as,  after  estimating  the  general 
strength  of  the  illumination,  to  guess  at  the  proper  exposures  by  reflecting  over  his  expe- 
rience for  the  particular  lens  and  diaphragm  which  he  is  about  to  employ,  would  simply 
need  to  learn  the  exposure  necessary  for  a  stop  of  f  20,  f  25,  for  any  lens  whatever.  It 
is  true  that  the  relation  of  the  diameter  of  the  stop  to  the  absolute  focal  length,  does  not 
fix  the  proportion  of  light  admitted  with  entire  accuracy,  but  it  does  so  sufficiently  to 
answer  all  practical  purposes.  When  the  stop  is  between  the  lenses,  the  proportion  of 
light  that  passes  through  it,  will,  to  some  extent,  depend  upon  the  construction  given  to 


68          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY, 

17.  Not  content  with  the  service  for  which  it  was  originally  devised  by  the 
optician,  the  thoughtful  photographer  has  suggested  other  uses  for  it,  and  other 
forms  of  construction  by.  means  of  which  these  new  uses  can  be.  made  practical 
and  easy  to  all. 

One  of  the  greatest  trials  of  the  landscape  photographer  is,  that  his  distance 
becomes  very  much  overexposed,  and  when  clouds  are  desired  they  are  lost 
before  sufficient  time  can  be  secured  for  his  foreground.  The  one  must  be 
sacrificed  in  some  degree  to  save  the  other. 

One  suggestion  to  help  this  comes  from  Mr.  Joseph  C.  Burritt.  It  consists 
simply  of  a  thin  brass  disk,  slit  in  the  centre  and  flared  out  at  top  and  bottom, 

the  front  lens.  But  variations  that  can  arise  in  this  way,  are  scarcely  sufficient  to 
diminish  the  practical  utility  of  the  principle  here  involved.  If  an  /23  diaphragm  re- 
quires with  a  given  light  an  exposure  of  a  given  number  of  seconds  with  one  lens,  it  will 
demand  the  same  approximately  with  any  other,  though  the  focal  length  be  longer  or 
shorter.  So  that,  if  this  improvement  were  adopted,  the  photographer  could  manage  any 
number  of  lenses  with  the  same  convenience  as  to  fixing  the  exposure,  as  if  he  always 
worked  with  one. 

A  feature  in  this  which  is  extremely  favorable  to  opticians,  is  that  it  would  immensely 
diminish  the  trouble  of  trying  new  lenses.  In  place  of  trying  various  stops,  experimental 
exposures,  and  so  forth,  the  photographer  would  be  able  to  give  the  right  exposure  at 
once,  even  with  a  lens  he  had  never  seen  before.  For,  knowing  that  with  a  given  light 
he  would  expose  ten  seconds,  let  us  say,  with  an  /20  stop,  he  would  do  the  same  with 
the  lens  under  trial  with  the  corresponding  stop,  and  be  spared  a  great  part  of  the  labor 
which  often  deters  photographers  from  experimenting.  Photographers  now,  moreover, 
feel  that  the  times  of  exposure  have  to  be  learned  for  each  new  lens,  and  the  employ- 
ment of  new  lenses  tends  to  confuse  the  experience  painfully  acquired  for  those  actually 
in  use.  This  is  by  no  means  all.  For,  if  stops  are  marked  by  figures  in  this  way,  we 
can  easily  estimate  comparative  exposures.  Then,  if  we  wish  to  pass  from  an/ 20  stop  to 
an  /25,  we  know  at  once  that  the  exposure  for  the  latter  must  be  a  little  over  one-half 
more  than  the  former.  For,  20  multiplied  by  itself  is  400 ;  and  25,  625.  The  ratio 
between  400  and  625  indicates  the  increased  exposure  necessary  in  the  former  case. — M. 
CAREY  LEA. 

17.  There  is  a  common  idea  prevalent  that  stops  to  lenses  are  arranged  upon  some 
regular  system,  and  that  they  are  suited  for  exposures,  each  one-half  longer  than  the 
next  larger  in  sequence ;  that  if  20  seconds  be  the  right  exposure  for  any  stop,  the  next 
smaller  must  have  30,  and  so  on.  This,  I  think,  is  not  the  case;  it  certainly  was  not  in 
any  determination  that  I  have  made.  For  example,  a  triplet  lens  showed  the  following 
relations  between  its  stops:  /m,/18£,/21,/27,/35J,/54. 

The  ratios  of  the  squares  of  these,  relations  to  which  the  exposures  must  be  directly 
proportioned,  are:  182.25;  353.44;  441;  729;  1242.56;  2916. 

It  will  be  seen  that  there  is  only  sufficient  regularity  to  mislead,  and  not  for  any  real 
utility. 


THE    DIAPHRAGM    OR    STOP. 


69 


the  former  being  flared  in  a  reverse  direction  from   the  latter.     It  will  be 
made  plain  by  the  engraving  (Fig.  52). 


FIG.  52. 


FIG.  53. 


FIG.  54. 


A  simple  slide  in  front  of  the  ordinary  diaphragm,  answers  a  very  good 
purpose. 

The  distance  between  this  slide  and  the  diaphragm  depends  much  on  the 
size  of  the  diaphragm,  and  also  on  the  width  of  the  angle  of  the  lens. 

Fig.  53  gives  a  front,  and  Fig.  54  a  side  view.  In  the  former,  A  is  the 
ordinary  diaphragm ;  B,  a  plate  for  holding  the  slide ;  C,  is  the  slide,  worked 
up  and  down  by  means  of  the  screw,  D,  outside  of  the  lens-tube. 

In  the  case  of  another  lens,  the  diameters  of  the  stops  were  found  to  be  £f ,  £f ,  ^f,  |-J,  f  f , 
of  an  inch. 

The  squares  of  the  numerators  of  these  fractions  are  respectively  225,  325,  529,  676, 
1296. 

To  be  in  the  ratio  of  one-half  longer  exposures,  these  numbers,  starting  with  the  first, 
should  be  225,  337,  505,  757,  1135. 

It  will  be  observed,  that  after  'the  first  three,  the  differences  are  material,  and  that 
throughout  they  are  sometimes  on  the  side  of  longer,  sometimes  of  shorter  exposure. 

If  these  relations  of  stops  to  focal  lengths  were  stamped  on  the  diaphragms,  photogra- 
phers would  soon  get  into  the  way  of  taking  them  habitually  into  account,  and  of 
expecting  a  certain  defining  power  with  an/ 20  stop,  and  so  on. 

If  any  one  will  be  at  the  pains  of  looking  at  the  information  given  as  to  exposures, 
with  the  processes  of  the  last  few  years,  he  will  perhaps  be  surprised  to  find  how  wholly 
useless  and  indefinite  it  is  in  the  great  majority  of  cases.  And  when  it  is  considered 
that  this  is  further  complicated  by  the  uncertainty  of  the  light,  it  will  be  felt  that  the 
information  given  is  just  nothing  at  all. 

But  if  a  writer  tells  us  that  his  process  receives  a  proper  exposure  by  25  seconds  of 
good  light  and  an/20  stop,  we  at  once  get  a  good  conception  of  what  is  the  comparative 
sensitiveness  of  his  method. — M.  CAREY  LEA. 


70          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

18.  Mr.  M.  Carey  Lea  and  Mr.  Thomas  Sutton  have  both  suggested  other 
forms  for  the  same  object.    Mr.  Lea's  plan  is  this,  Fig.  55.     The  figure  drawn 

inside  of  the  circle,  which  indicates  the  size  of  the  lens, 
FIG  55.  ' 

represents  a  set  of  narrow  parallel  bars  connected 

by  a  transverse  bar.  This  is  cut  out  of  soft,  dark 
blotting-paper,  not  sized  paper,  and  is  attached  to 
the  lens  itself,  with  the  aid  of  a  little  paste.  It  is 
used  upon  a  view  lens,  the  lower  half  of  which  it 
thus  partly  covers.  The  bars  must  not  be  too  wide 
nor  too  near  together. 

Their  proper  size  will  always  depend  upon  that 
of  the  diaphragm  with  which  they  are  used ;  each 
bar  and  each  space  between  two  bars  must  be  less 
than  half  the  diameter  of  the  stop  used,  otherwise  a  shadow  will  be  produced, 
and  will  show  itself  on  the  ground-glass  and  in  the  negative.  When  this 
cross-barred  diaphragm  is  properly  made  and  properly  applied,  it  does  not 
appear  at  all  upon  the  ground-glass,  and  its  effect  is  only  to  diminish  largely 
the  illumination  of  the  sky. 

Mr.  Button's  invention  has  several  advantages. 

The  idea  is  simply  that  the  plate  in  which  the  stop  is  pierced,  shall  be 

18.  Many  are  disappointed  in  the  small  amount  of  information  obtainable  regarding 
exposures. 

This  can  be  easily  remedied  by  representing  the  size  of  our  stops  in  terms  of  the  focal 
length  of  the  lens. 

Expressing  the  size  of  the  stops  by  their  diameters,  as  is  frequently  done,  is  only  mis- 
leading ;  and  unless  the  focal  length  is  given  is  of  no  practical  use. 

A  half-inch  stop,  used  on  a  lens  with  an  equivalent  focus  of  twelve  inches,  would 
require  four  times  the  exposure  that  the  same  stop  would  require  on  a  lens  of  six-inch 
equivalent  focus.  As  the  rapidity  of  lenses  is  controlled  by  their  equivalent  focal  lengths, 
and  also  by  their  apertures,  no  "  scientific  "  or  "  universal "  system  of  stops  can  be  made, 
except  one  based  on  these  two  elements ;  the  ratios  between  the  areas  of  apertures  and 
duration  of  exposures  having  been  determined  by  careful  experiments.  In  order  to 
correct  a  very  general  misunderstanding  regarding  what  is  called  equivalent  focus  and 
how  it  is  obtained,  it  may  be  advisable  to  state  that  the  expression  is  used  in  connection 
with  compound  lenses,  and  means  a  focus  of  some  distant  object  equal  to  that  produced 
by  a  single  plano-convex  lens,  with  the  plane  side  toward  the  object,  producing  an  image 
of  the  same  distant  object  of  the  same  size.  In  the  case  of  the  plano-convex  lens,  we 
can  easily  measure  its  focal  length  by  measuring  the  distance  from  the  image  on  the 
ground-glass  to  the  convex  surface  of  the  lens.  In  compound  lenses,  however,  this  will 
not  give  us  the  true  focal  length,  but  what  is  usually  called  the  "back  focus."  The 


THE    DIAPHRAGM    OR    STOP. 


71 


FIG.  56. 


incMned,  instead  of  being,  as  usual,  at  right  angles  with  the  axis  of  the  lens. 
Thus,  the  beam  of  light  admitted  from  the  foreground  corresponds  with  the 
full  size  of  the  diaphragm,  whilst  that  from  the  upper  part  of  the  picture  is 
greatly  reduced  in  size.  The  inventor  calculates,  that  by  inclining  the  stop  at 
an  angle  of  35  degrees,  the  proportion  of  light  admittted  from  the  foreground 
will  be  four  times  that  from  the  sky. 

Thus,  the  sky  portion  of  the  picture  is  kept  back,  and  time  allowed  for  the 
foreground  to  impress  itself. 

The  mechanical  contrivance  to  effect  this  object,  consists  of  a  tube  of  metal 
slightly  conical,  and  of  a  size  to  pass  by  its  smaller  end  into  the  largest  of  the 
stops,  and  by  reason  of  its  conical  form,  to  catch  fast  when  passed  half  way  up. 
Inside  of  this  conical  tube  is  a  piece 
of  metal  which  occupies  an  inclined 
position,  .and  in  it  an  opening  is  made 
of  such  size  as  is  judged  proper;  it 
should  have  the  same  diameter  as  that 
of  the  stop  with  which  the  lens  is  most  ^~ 
commonly  used,  or  may  exceed  this  by 
a  little. 

In  Fig.  56,  1,  the  inclined  stop  is 
seen,  and  the  much  larger  beam  that  it 
admits  from  below  than  that  from  above. 
(By  a  mistake  of  the  engraver,  the  larger 
beam  has  been  made  conical,  to  the 
right  of  the  lens.  Its  sides  should,  of 
course,  be  parallel,  like  those  of  the 

smaller  beam.)  In  Fig.  56,  2,  the  conical  tube  is  seen  with  the  inclined  plate 
and  the  opening  of  the  stop  cut  in  it.  Fig.  56,  3,  is  a  section  of  the  same 
when  set  in  place. 

equivalent  focus  of  a  compound  lens  is  the  distance  from  the  image  on  the  ground-glass 
of  some  very  distant  object,  to  a  point  within  the  lens  called  the  centre  of  emission. 

This  point  is  obtained  by  a  formula  based  upon  the  radii  of  the  curves  of  the  different 
lenses,  and  the  refractive  power  of  the  materials  used  in  the  lenses.  Fortunately  it  is 
not  necessary  for  us  to  use  the  formula,  for  the  equivalent  focus  of  any  form  of  lens  can 
be  easily  obtained  in  the  following  manner : 

Mark  two  perpendicular  lines  on  the  ground-glass  equidistant  from  the  centre.  Set 
the  camera  on  a  sheet  of  paper  and  focus  on  some  point  in  a  very  distant  object.  Move 
the  camera  so  that  this  point  will  fall  upon  one  of  the  lines  on  the  ground-glass.  Draw 


72 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


The  inventor  suggests  a  second  advantage,  that  even  when  it  is  not  desired 
to  attempt  clouds,  or  when  there  are  none  to  attempt,  it  may  frequently  happen 
that  if  we  suppose  the  view  to  he  divided  by  a  diagonal  line,  one  of  the  parts 
will  be  much  less  illuminated  than  the  other,  and  tend  to  produce  too  great 
a  contrast  in  the  negative.  In  such  a  case,  he  would  propose  to  turn  the  stop 
round  to  an  angle  of  45  degrees.  Thus,  of  the  light  coming  from  the  less 
illuminated  part,  a  much  larger  proportion  is  admitted,  and  a  useful  approxi- 
mation to  equalization  is  obtained. 

FIG.  57. 


Disks  of  tin  foil  or  ferrotype  plate  may  be  cut  similar  to  the  designs  repre- 
sented in  Fig.  57,  and  placed  at  the  back  of  the  lens ;  and  though  largely 
increasing  the  exposure,  the  use  of  such  has  been  found  in  portraiture  to  secure 
a  much  rounder  figure.  This  is  easy  to  understand. 

19.  Mr.  M.  M.  Griswold,  some  time  ago,  suggested  an  "illuminated77  stop, 

a  pencil  along  the  side  of  the  camera,  ruling  a  line  on  the  paper  underneath.  Now 
partially  rotate  the  camera  on  a  centre  passing  through  the  centre  of  the  lens,  until  the 
point  falls  upon  the  other  line  on  the  ground-glass,  and  draw  another  line  on  the  paper. 
Extend  these  two' lines  until  they  meet.  Bisect  this  angle  with  a  line  upon  which  you 
erect  a  perpendicular  equal  in  length  to  one-half  the  distance  between  the  two  lines  on 
the  ground-glass.  Connect  the  top  of  this  perpendicular  and  the  bisecting  line  with  a 
line  parallel  with  the  side  of  the  angle.  The  distance  from  the  point  where  this  line 
touches  the  bisecting  line  to  the  foot  of  the  perpendicular  is  the  absolute  focal  length  of 
the  lens  used.— C.  W.  DEAN. 

19.  The  object  in  focussing  upon  a  very  distant  object  is  that  we  may  obtain  the  focus 
from  parallel  rays.  This  focus  is  represented  by  f,  and  of  course  is  entirely  different 
from  the  focus  of  converging  rays  from  an  object  near  the  lens.  A  practical  fact  regard- 
ing the  equivalent  focus  of  the  lens  is  that  it  controls  the  size  of  the  image ;  that  is,  two 
lenses  of  the  same  equivalent  focus,  when  focussed  upon  any  distant  object,  will  produce 
images  of  the  same  size.  A  lens  having  twice  the  focal  length  of  another,  when  placed 
in  the  same  spot  and  focussed  upon  the  same  distant  object,  will  produce  an  image  having 
twice  the  linear  dimensions  of  the  image  given  by  the  first.  Having  obtained  the  equiv- 
alent focus  of  the  lens,  we  can  designate  our  stops  in  terms  of  (  by  means  of  a  fraction, 
the  numerator  of  which  is  equal  to  the  diameter  of  the  stop,  and  the  denominator  is 
equal  to  the  equivalent  focus  of  the  lens.  Reducing  this  fraction  to  an  equivalent,  one 


THE    DIAPHRAGM    OR    STOP.  73 

by  the  use  of  which  he  accelerated  the  exposure  of  the  negative.  He  made  it 
of  photographic  paper,  rendered  translucent  by  castor  oil,  and  substituted  it  for 
the  ordinary  diaphragm.  By  experiment  he  found  that  red  was  the  best  color 
for  the  paper  stop,  and  by  using  such  a  stop  he  diminished  the  exposure  very 
materially,  without  increasing  the  size  of  the  stop,  and  without  any  detriment 
to  the  sharpness  of  the  image. 

Photographs  made  with  the  illuminated  stop  have  no  harsh  contrasts,  but 
fine  detail,  and  a  tendency  to  great  softness. 

The  necessity  of  quickly  changing  the  diaphragms  has  excited  the  inventive 
genius  of  some  of  our  opticians,  too.  Mr.  Schnitzer  devised  one  composed  of 
six  wings  which  opened  and  shut  toward  a  common  centre.  Some  of  the 
recently  invented  "drop  shutters  "  are  upon  the  same  principle,  and  serve  both 
as  a  shutter  and  as  a  stop.  As  a  rule,  the  holes  are  not  round.  Mr.  Joseph 
Zeiitmayer's  adjustable  diaphragm  gives  a  round  aperture.  It  consists  of  two 
rollers  of  the  same  diameter,  geared  together  by  delicate  cog-work,  so  that  they 
revolve  upon  each  other.  On  each  roller,  in  a  plane  perpendicular  to  the  axis, 
a  tapering  semicircular  groove  is  cut,  the  corresponding  parts  of  each  groove 

whose  numerator  is  unity,  we  have  a  fraction  which  means  that  the  diameter  of  the  stop 
is  one-eighth,  one-twentieth,  or  one-fortieth,  as  the  case  may  be,  of  the  focal  length  of 
the  lens. 

To  show  that  this  focal  length  is  the  one  from  parallel  rays,  the  fraction  is  usually 
written  |,  /^,  ^j. 

Having  marked  our  stops  in  terms  of  their  focal  length,  we  can  approximately  determine 
the  relative  duration  of  exposure  required  by  each  by  remembering  that  these  fractions 
represent  the  diameter  of  aperture  whose  areas  are  to  each  other  as  the  squares  of  these 
diameters ;  and  that  approximately  the  duration  of  exposure  is  inversely  as  the  areas  of 
the  stops ;  for  example,  to  ascertain  the  relative  time  required  by  two  stops,  Tf^  and  /^j,  the 
area  of  the  first  can  be  represented  by  (TIT)*  =  TO  <r>  an^  tne  second  by  GV)2  =  irkr-  This 
shows  that  the  first  stop  is  nine  times  as  large  as  the  second,  and  requires  approximately 
one-ninth  the  time  for  exposure. 

The  same  result  is  obtained  by  dividing  one  fraction  by  the  other  and  squaring  the 
result. 

While  the  above  rules  will  assist  us  in  obtaining  correct  exposures  with  the  different 
size  stops,  an  equally  important  question  is,  "  Which  stop  shall  I  use  ?"  Up  to  certain 
limits,  the  smaller  the  stop  the  greater  the  sharpness,  depth  of  focus,  and  size  of  good 
picture  obtained.  The  small  stop,  however,  produces  a  map-like  effect,  and  tends  to 
harshness  of  contrast  and  to  diminish  aerial  perspective. 

Some  opticians  say  that  the  diameter  of  the  smallest  stop  should  never  be  less  than 
one-twenty-fifth  or  one-thirtieth  the  focal  length  of  the  lens.  On  the  other  hand,  the 
larger  the  stop  (if  correctly  exposed)  the  greater  the  amount  of  detail  in  the  shadows, 
and  the  bolder  the  picture,  and  the  greater  the  amount  of  "  atmosphere." 


74          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

being  opposite.  Then,  by  revolving  the  rollers,  the  circular  opening  formed 
by  the  contact  of  the  two  tapering  grooves  enlarges  or  contracts,  depending 
upon  the  direction  in  which  the  rollers  are  turned,  the  rollers  being  so  accu- 
rately set  together  that  no  light  can  pass,  except  through  the  diaphragm.  The 
motion  is  so  gradual,  that  unless  some  form  of  index  is  used,  it  would  be  next 
to  impossible  to  twice  obtain  exactly  the  same  size  of  opening. 

FIG.  65.  FIG.  66. 


Applied  to  the  microscope,  this  plan  answers  perfectly.  Used  as  a  diaphragm 
in  double  combination  photographic  lenses,  it  would,  in  some  cases,  be  objection- 
able, although  of  advantage  in  single-view  lenses.  The  cause  of  difficulty  is, 
that  the  diaphragm  will  not  remain  permanent  in  the  same  plane. 

In  the  chapter  on  "  Exposure,"  further  help  may  be  had  in  this  matter. 

Probably  the  best  rule  to  adopt  is  to  use  a  stop  small  enough  to  give  sharp  definition 
at  the  edges  of  the  picture,  and  no  smaller.  To  secure  uniformity  in  our  work,  and 
enable  us  to  aid  each  other  in  answering  that  vexing  question,  "  How  long  shall  I 
expose?"  I  would  suggest  that  the  stops  be  marked  in  terms  of  -,  and  also  with  a  figure 
representing  the  approximate  relative  value  of  the  stop  as  compared  with  the  full  opening 
of  the  lens  with  which  it  is  used.  For  example,  a  stop  marked  7^  would  mean  that  the 
stop  requires  seven  times  the  exposure  of  the  full  opening  of  the  lens,  and  the  diameter 
of  the  stop  is  equal  to  one-twenty-second  of  the  focal  length  of  the  lens. 

As  most  of  us  use  lenses  working  no  faster  than  £,  the  adoption  of  the  "universal" 
system,  based  on  |,  would  necessitate  an  amount  of  mental  arithmetic  which  some  of  us 
might  consider  tiresome.  In  this  system,  the  first  figure  would  show  the  relative 
exposure  as  compared  with  the  other  stops ;  while  the  fraction  would  show  the  rapidity 
of  the  lens  as  compared  with  other  lenses. 

By  adopting  this  system,  we  are  able  to  obtain  correct  exposures  with  any  lens, 
regardless  of  the  maker  or  its  form. — C.  W.  DEAN. 

Always  use  the  largest  possible  stop  in  order  to  secure  vigor,  roundness,  and  atmos- 
pheric effect  in  the  picture.  A  small  stop  produces  sharpness,  but  at  the  expense  of 
the  foregoing  essential  qualities.  As  a  rule,  focus  for  some  prominent  object  in  the 
foreground,  or  upon  that  which  is  to  constitute  the  point  of  interest  in  the  picture.  Do 
this  with  a  medium  stop,  then  insert  the  next,  or  the  next  but  one  smaller,  sufficient  to 
prevent  objects  not  focussed  upon  appearing  too  much  blurred. — J.  H.  DALLMEYER. 


CHAPTER   VII. 


FIG.  67. 


GLASS-HOUSE   CONSTKUCTION. 

20.  As  our  art  progresses,  more  and  more  interest  seems  to  be  taken  in  the 
construction  of  the  glass-house.  How  to  secure  the  best  mode  of  lighting  the 
model,  and  how  to  construct  the  atelier,  have  become  quite  as  important  ques- 
tions as  what  lenses  or  developers  are  best.  The  idea  that  "  any  room  with  a 
top  or  side  light  in  any  convenient  locality  and  direction  is  good  enough  for 
making  pictures,"  is  exploded,  and  there  is  a  growing  desire  among  artists  to 
find  out  the  best  way  to  construct  their  lights  in  order  to  secure  the  best  results. 

The  thing  of  first  importance  is  to  select  the  locality  for  the  glass-house. 
This  should  be  done  with  much  care.  One  should  not  disregard  the  fact  that 

20.  If  we  wish  to  find  out  how  much  light  there  is  at  any  given  point  in  the  glass- 
house, we  only  need  to  determine  how  large  a  piece  of  the  sky  illuminates  this  point. 

If  we  take,  for  instance,  a  room  like  the  annexed  figure,  inclosed  on  all  sides  by  a  wall 
and  on  the  one  side  a  window  be;  if  we  take  further  different  points  in  the  room,  as 
a,  d,  e,  a',  then  the  amount  of  light  which  any  one 
of  these  points  receives,  will  be  proportionate'  to 
the  distance  and  position  in  regard  to  the  window. 
The  point  a',  which  is  more  distant  from  the  win- 
dow, will  appear  darker  than  a,  and  a  will  again 
appear  lighter  than  the  points  d  or  e,  which  are  the 
"same  distance  from  the  window,  but  not  opposite 
to  it. 

If  we  wish  now  to  find  out  positively  the  amount 
of  light  which  a  certain  point  receives,  it  will  be 
necessary  to  draw  lines  from  this  point  to  the  cor- 
ners of  the  window  b  and  c;  the  angle  which  is 
thus  formed,  or  the  angle  of  light,  gives  a  criterion 
of  the  size  of  the  piece  of  the  sky  which  illuminates 
this  point.  Following  this  construction,  a  glance 
at  the  figure  will  show  that  the  angle  of  light 

which  we  obtain  for  a'  is  smaller  than  for  a,  and  again,  the  angle  at  a  is  larger  than  at 
d,  and  d  again  larger  than  e.  If  we  take  a  point  on  the  wall  containing  the  window,  the 
angle  will  be  reduced  to  a  line.  Such  a  point  would,  therefore,  be  absolutely  dark,  if  it 
was  not  illuminated  by  reflection  from  the  wall. 

(75) 


76 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


the  quality,  and  not  the  quantity  or  intensity  of  the  light,  is  the  great  require- 
ment to  be  sought  for.  A  strong  light  produces  unpleasant  and  inartistic 
shadows,  and  contracts  the  features  of  the  model.  Consequently,  the  direct 
action  of  the  sun's  rays  and  all  reflections  from  adjacent  buildings  should  be 
avoided 

21.  Having  then  secured  a  proper  place,  how  shall  we  build  the  glass-room? 
One  part  should  be  open  to  the  north,  another  to  the  east,  a  third  to  the  west, 
and  the  south  side  should  be  closed.  In  many  cases  it  will  be  found  impossible 
to  have  a  side  light ;  but  if  this  be  so,  care  should  be  taken  that  the  inclination 
of  the  top  light  is  toward  the  north.  It  would  be  better  to  elevate  the  room, 
even  a.  story  higher,  to  get  one  side  light  at  least  In  fact,  it  is  almost  a 
necessity  that  the  model  should  face  the  north,  in  order  that  there  need  be  no 
contraction  of  the  features  by  a  too  powerful  light.  Even  should  a  dark  wall 
be  at  the  north  of  the  room,  the  sitter  should  face  it  or  nearly  so,  and  the  south 
should  be  obscured. 

Fig.  69  is  a  diagram  of  a  typical  American  glass-room.  It  has  proved  to  be 
one  of  the  very  best  arrangements  and  a  safe  model  to  go  by.  The  view  given 

For  small  windows,  we  have  the  law  that  the  illumination  of  a  point  is  at  the  inverse  rate 
of  the  square  of  its  distance  from  the  window. 

When  the  window  is  larger,  the  light  does  not  decrease  with  the  same  rapidity.  At 
first  sight  these  principles  will  appear  as  mere  theoretical  trash;  I  shall,  however, 

endeavor  to  draw  some  practical  conclusions  from  them. 
I  take  a  glass-house,  the  glass-side  of  which,  S'  S,  admits 
of  being  closed  by  curtains ;  I  take,  further,  a  point  a', 
which  receives,  through  an  opening  in  the  curtain  b  i. 
just  sufficient  light  for  taking  a  portrait,  then  b  of  'i 
would  be  the  angle  of  light  for  this  point. 

If  I  take  now  a  second  point  a",  to  which  I  desire 
to  give  the  same  amount  of  light,  without  being  able  to 
move  the  spot  from  its  place;  in  this  case  the  angles  of 
light  b  a"  i  would  be  much  smaller,  and,  in  order  to 

obtain  the  same  amount  of  light  for  a//  as  for  a',  the  opening  in  the  curtain  would  have 
to  be  enlarged  until  the  two  angles  coincide. 

I  have  met  with  many  photographers  who  do  not  even  understand  these  simple  and 
easy  rules,  and  who  vainly  attempt  to  take  pictures  at  a//  in  the  same  time  and  with  the 
same  effect  as  at  a'. — DR.  H.  W.  VOGEL. 

21.  There  is  more  art  in  lighting  the  model  than  most  are  willing  to  concede.  A  mild, 
soft  light  is  what  is  required.  A  strong  illumination  produces  shadows  of  great  intensity, 
and  often  contracts  the  features  of  the  model.  This  is  why  some  people  complain  that 
their  pictures  make  them  look  older  than  they  really  are. — GEORGE  H.'  FENNEMORE. 


Fm  68. 


GLASS-HOUSE    CONSTRUCTION. 


77 


of  it  is  from  the  east  side,  thus  showing  the  arrangement  of  the  top  and  one 
side.     Of  course,  then,  the  side  we  see  is  the  west  side ;  by  the  chair  we  observe 


FIG.  69. 


where  the  model  is  placed,  and  the  camera  and  stand  point  out  the  space  near 
which  they  are  used.     The  dimensions  of  the  room  are  as  follows : 

Width  of  side  light ]  3  feet. 

Height  of  side  light  at  the  lowest  point  ....  6  feet  10  inches. 
Height  of  side  light  at  the  highest  point  .  .  .  .11  feet  9  inches. 
Distance  from  the  floor  to  the  bottom  of  the  side  light  .  14  inches. 

Width  of  the  top  light 17  feet  6  inches. 

Length  of  the  top  light .15  feet. 

Depth  of  the  room  as  shown  in  the  diagram        .        .        .32  feet. 

It  will  be  seen  that  instead  of  blinds,  curtains  or  shades  are  used  to  modify 
the  light  at  the  top  and  on  both  sides.  By  a  proper  arrangement  of  weights, 
pulleys,  etc.,  they  are  made  to  change  the  light  as  the  operator  may  desire.  If 
the  light  be  too  strong  from  the  direction  of  the  top  or  side,  the  curtains  are 
drawn  so  as  to  soften  the  shadows,  and  secure  such  relief  as  is  found  requisite. 
These  curtains  can  be  raised  or  lowered  to  any  extent ;  so  it  will  be  seen  that 
by  their  use  almost  any  modification  of  light  can  be  secured.  They  may  be 
made  of  blue  or  white  muslin,  and  therefore  admit  only  the  kind  of  light 


78 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


needed.  Experience  must  teach  the  proper  use  of  them.  On  days  when  the 
sun  shines  directly  upon  or  in  the  room,  the  whole  of  the  curtains  should  be 
drawn  over,  and  at  other  times  they  may  be  arranged  variously,  somewhat  as 
they  appear  in  the  diagram. 

22.  Where  an  extensive  business  is  done,  and  the  floor  is  large  enough,  a 
studio  like  this  could  be  divided  by  a  heavy  curtain,  and  thus  two  complete 
skylights  secured,  one  with  an  east  side  light  and  the  other  with  a  western 
exposure.  The  advantages  of  such  a  plan  are  obvious. 

Where  the  construction  cannot  be  as  above,  much  the  same  advantages  may 
be  had  by  adopting  a  modification  of  it.  In  Fig.  70,  the  top  and  side  light 

FIG.  70. 


are  both  from  the  north,  and  the  room  is  so  planned  that  the  background  may 
be  used  in  the  east  or  in  the  west,  at  will.  The  models  shown  are  quite  low, 
and  formerly,  when  wet  plates  were  most  used,  this  was  an  object,  because  it 
accelerated  the  exposure. 

s 

22.  Every  portraitist  of  experience  knows  very  well  that  the  best  results  are  got  in 
diffused  light,  not  direct,  and  that  is  obtained  from  the  front,  top,  and  side  lights,  or  the 
farthest  corner  through  which  the  light  is  admitted,  no  matter  whether  the  gallery  has  a 
flat,  or  span,  or  side  sloping  roof.  Direct  top  light  is  wrong,  likewise  direct  side  light. 
In  studios  built  with  side  light  only,  the  best,  or,  rather,  the  most  pleasing  pictures  are 
made  by  placing  the  model  on  one  side  of  the  background,  the  farthest  from  the  source 


GLASS-HOUSE    CONSTRUCTION.  79 

23.  A  more  diffused  light  may  be  obtained  by  a  higher  construction,  but  its 
use  also  requires  a  higher  degree  of  skill.  The  plan  represented  in  Fig.  71  is 
engraved  from  the  studio  of  Mr.  J.  H.  Kent,  Rochester,  New  York.  It  will 


FIG.  71. 


be  seen  that  the  side  light  leans  or  is  inclined  somewhat,  a  plan  by  which  Mr, 
Kent  believes  he  secures  advantages  in  grading  the  light  upon  the  lower 
draperies  and  accessories.  Mr.  Kent  uses  the  handscreen  to  modify  the  light 
during  exposure.  This  is  explained  in  the  next  chapter. 

of  light ;  those  with  top  light  only,  by  shading  the  sitter  over  the  head.  An  operator 
once  said :  "  We  take  sitters  from  the  front,  therefore  the  front  should  be  the  PREDOMINANT 
LIGHT."  Another  operator  said :  "  I  should  put  it  thus :  therefore  we  want  the  predomi- 
nant light  from  the  side.  People  do  not  take  a  landscape  or  a  building  with  the  sun 
plump  behind  the  camera." 

,  I  say  that  depends  upon  circumstances ;  it  is  convenient  (and  I  speak  from  much 
experience)  at  times  to  get  the  sun  "  plump  behind  the  camera." — DAVID  DUNCAN. 

23.  A  top  side  light  is  the  best  combination.  The  most  common  error  in  skylights  is 
the  height.  In  many  cases  this  is  from  choice,  as  high  lights  have  their  advocates,  who 
sustain  them  from  theory  rather  than  from  practice ;  in  many  others  it  is  from  necessity 
arising  from  the  construction  of  the  building,  which  cannot  be  altered.  But  a  photog- 


80  WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 

24.  Mr.  James  Landy,  Cincinnati,  Ohio,  inclines  his  side  light  still  more, 
and  uses  it  variously  as  a  top,  side,  and  even  front  light,  according  to  the 
subject  in  hand.  It  is  peculiarly  adapted  for  "  shadow  "  and  "  Rembrandt " 
effects,  ana  for  "  statuary  "  pictures  as  well.  With  a  well-constructed  skylight 
in  the  top  of  the  operator's  cranium,  such  a  studio  construction  will  help  to 
almost  any  sort  of  lighting  the  heart  c'ould  desire.  (Fig.  72.) 

FIG.  72. 


The  dimensions  of  this  studio  are  as  follows  :  Length  40  feet,  width  25  feet, 
top  and  side  light,  each  12  feet  wide.  The  side  light  reaches  to  within  2 

rapher  had  better  reject  a  location  altogether  than  accept  it  with  an  unfavorable  light, 
for  success  depends  upon  that  more  than  upon  any  other  part  of  the  gallery. 

The  loss  of  light,  which  is  the  principal  objection  to  a. high  skylight,  may  be  (Com- 
pensated for  by  making  the  light  proportionately  larger.  As,  for  instance,  suppose  a 
light  sixteen  feet  square  and  eight  feet  high  above  the  head  of  the  sitter ;  the  latter  would 
receive  the  same  amount  of  light  above  an  angle  of  forty-five  degrees  as  under  a  light 
twenty-four  feet  square  and  twelve  feet  high ;  but  place  the  sixteen  feet  light  at  the 
height  of  twelve  feet,  and  there  will  be  a  loss  of  fifty  per  cent,  in  the  amount  of  light 
admitted  to  the  sitter. 

Thus  it  is  clearly  to  be  seen,  as  all  practice  proves,  that  a  high  light  will  work  slow 
compared  with  a  low  light  of  the  same  size. — E.  J.  CHUTE. 

24.  Fig.  73  is  a  longitudinal  section  of  an  ordinary  ridge-roof  studio,  30  feet  long,  9 
feet  high  to  the  eaves,  and  5  feet  from  level  of  eaves  to  ridge,  making  in  all  14  feet.  Six 
feet  from  the  background,  over  the  head  of  the  model,  is  opaque.  The  skylight  is  10  feet 
long,  and  the  remainder  of  the  roof  is  opaque.  A  is  the  model,  6  feet  high,  and  the 


GLASS-HOUSE    CONSTRUCTION. 


81 


feet  6  inches  of  the  floor,  stands  at  an  angle  of  about  25  degrees,  and  is 
10  feet  high.  The  top  light  is  20  feet  long,  and  inclined  at  an  angle  of 
40  degrees.  In  a  skylight  of  this  construction  one  may  obtain  almost  any 
effect  desired,  especially  when  helped  by  the  appliances  which  are  suggested 
further  on. 

dotted  lines  B  B  drawn  from  his  head  and  feet,  and  cutting  the  roof  at  the  extreme  ends 
of  the  skylight,  show  the  quantity  of  "  direct "  light  he  is  capable  of  receiving  from  that 


FIG.  73. 


Fro.  74. 


FIG.  75. 


source ;  C  is  the  sun,  who  very  unceremoniously  floods  the  camera  end  of  the  studio  with 
his  rays  (D  J9),  tormenting  the  unfortunate  operator  almost  beyond  endurance.  A  quan- 
tity of  light  also  descends  vertically  into  the 
room. 

Fig.  74  is  similar  to  Fig.  73,  with  this  excep- 
tion, the  dotted  line  B,  from  the  head  of  the 
model,  through  the  skylight,  which  was  only 
imaginary  in  Fig.  73,  has  become  an  opaque 
sunshade,  or  shield,  which  effectually  prevents 
the  sun  from  entering  the  studio.  As  it  is  car- 
ried up  to  a  point  exactly  above  the  extreme 
end  of  the  skylight,  it  also  cuts  off  the  whole 
of  the  vertical  rays  which  fell  upon  the  floor, 
and  being  reflected  in  various  directions,  do 
their  best  to  destroy  the  brilliancy  of  the  pic- 
ture; in  fact,  a  number  of  the  obnoxious  "jets" 
are  extinguished  without  in  any  way  inter- 
fering with  the  direct  north  light  which  still  falls 
upon  the  model  at  the  same  angle  as  at  first. 

If  this  method  of  lighting  is  good  for  the  skylight,  it  is  also  good  for  the  side  lights 
(I  mean  windows  in  the  sides  of  the  studios).  Shade  these  in  the  same  manner,  being 
careful  not  to  interfere  with  the  direct  north  light,  and  the  lens,  no  longer  having  to 

6 


n 


\  B 


82 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


25.  In  some  of  the  colder  sections  of  our  country,  where  snow  is  plentiful,  a 
cone  light  is  used.  Such  a  plan  is  described  and  illustrated  in  Wilson's 
Photographies.  Another  method,  adopted  somewhat  in  Canada,  is  to  use  a 
flat  top  light  inside. 

FIG.  76. 


Fig.  76  represents  a  skylight  which  is  50  feet  long,  20 J  feet  wide,  and  14 
feet  high  from  the  floor  to  the  flat  light  above.  The  side  light  is  10 J  feet 

fight  its  way  through  a  fog  to  get  at  the  model,  will  gratefully  express  its  sense  of  relief 
by  the  increased  brilliancy  of  the  image  projected  upon  the  plate. 

Fig.  75  shows  the  shape  of  the  roof  shield  (A  A  A  A],  and  also  the  angles  of  the 
side  shields  and  their  distance  from  the  house.  These  may  commence  at  the  south  end 
of  the  studio,  or  at  the  junction  of  the  dotted  lines  with  the  skylight.  B  B  show  the 
angle  of  direct  side  light  falling  upon  the  sitter  to  be  exactly  the  same  as  if  the  shields 
were  not  there. 

To  carry  this  plan  out  in  its  integrity,  a  plot  of  ground  37  feet  by  30  feet  would  be 
required.  Where  this  is  not  available,  the  top  shield  alone  may  be  used. — R.  A. 

25.  Having  had  some  recent  experience  in  working  a  high  side  light,  I  was  much 
pleased  with  the  results  secured  by  it.  It  was  about  twelve  feet  square,  and  situated  due 
north.  I  ran  a  blue,  opaque  curtain  across  the  bottom,  so  that  the  top  of  it  was  about 


GLASS-HOUSE    CONSTRUCTION.  83 

high,  by  15  feet  wide.  The  flat  top  light  is  15  feet  square.  Over  this  flat 
light  there  is  a  sloping  top  or  roof  light,  15  feet  wide,  and  about  13  feet  deep. 
As  the  slope  is  rather  steep,  and  there  is  snow  upon  it  much  of  the  time,  the 
flat  light  is  introduced  to  prevent  leakage  during  the  melting  season.  The 
studio  stands  due  north,  and  both  ends  of  the  room  are  used. 

26.  In  Europe  one  finds  much  less  attention  paid  to  skylight  construction 

four  and  a  half  feet  from  the  floor.  Above  this  were  two  breadths  of  white  muslin 
curtains,  running  on  wires  so  as  to  be  readily  adjusted  to  the  requirements  of  the  light  or 
sitter.  On  the  shadow  side  I  placed  a  screen  of  a  light  neutral  tint,  which  being  moved 
near  or  far  from  the  subject  produced  the  desired  effect.  In  addition  I  ran  a  white 
curtain  on  a  wire  across  this  side  screen,  at  about  the  height  of  the  sitter's  head,  for  the 
purpose  of  lighting  up  dark  or  tanned  faces.  This  light  for  single  heads  I  found  to  work 
remarkably  well,  producing  negatives  as  well  lighted  and  of  as  fine  modelling  as  could 
be  produced  under  most  of  the  combination  lights. — R.  J.  CHUTE. 

26.  Beware  of  too  much  light.  The  reflections  from  a  variety  of  objects,  and  the  light 
from  a  mass  of  illuminated  atmosphere  reaching  the  lens,  instead  of  the  light  only  from 
the  objects  forming  the  picture,  must  necessarily  tend  materially  to  destroy  brilliancy. 

There  are  many  ways  in  which  the  lens  can  be  protected  from  false  lights.  Many 
persons  inclose  the  camera  in  a  travelling  dark-room.  Others  use  a  cone  in  front  of  the 
lens,  projecting  about  a  foot.  Mr.  Eobinson,  in  his  admirable  article  on  the  "  Glass- 
room,"  provides  for  the  light  chiefly  reaching  the  sitter,  but  he  also  employs  such  a  cone 
as  I  have  described.  Some  photographers  darken  permanently  one  end  of  the  dark- 
room, and  some  even  resort  to  the  use  of  an  unsightly  tunnel. 

Every  studio  should  possess  ample  facility  for  removing  all  unnecessary  light,  without 
in  any  way  interfering  with  comfort  and  elegance. — G.  WHARTOIST  SIMPSON. 

Another  query :  Which  is  most  practical  for  portraiture — a  high  or  a  low  glass-house  ? 

Suppose  D  (Fig.  77)  is  the  glass  roof,  with  an  opening  c,  at  a  distance  of  about  twelve 
feet  from  the  floor  B  B/ ;    a'  a"  is  a  standing  figure ;  then  the  angle  d  and  e  would 
determine  the  quantity  of  light  which  head  and  feet  would 
receive  through  the  opening  c ;  if  we  now  take  a  glass-house 
of  twice  the  height,  i.  e.,  the  floor  at  J5X/  B"  and  the  figure 
at  a'"  a///x,  then  f  and  g  are  the  corresponding  angles  of 
light ;  a  glance  at  the  figure  will  show  (still  better  a  simple  /  _ 

mathematical  consideration)  that  the  angles /and  g,  and  d 
and  e,  differ  very  slightly,  and  hence,  it  follows,  that  in  a 
very  high  glass-house,  head  and  feet  receive  nearly  the  same 
amount  of  light,  and  a  person  is  evenly  illuminated  from       B'      dill 
head  to  feet. 

The  difference  in  a  low  glass-house  is  much  greater;  then 
the  difference  between  the  angles  is  more  noticeable,  and  the 
angle  d  at  the  head  is  larger  than  the  angle  e  at  the  feet.     R// 
The  question  is,  Which  is  the  most  profitable? 

In  a  portrait  the  head  is  undoubtedly  of  first  importance ;  it  ought  to  receive  the 
principal  light,  and  all  the  other  parts  can  be  kept  in  a  half  light ;  for  portraiture, 


84 


WILSON'S    QUAKTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  78. 


than  in  America.  One  of  the  reasons  for  this  is  because  of  the  crowded 
quarters  with  which  the  photographer  must  be  content  in  many  localities. 
Many  studios  are  in  the  form  of  an  annex  to  some  great  structure — a  hotel,  for 
example,  and  on  the  roof. 

One  of  the  best  models  is  that  of  Mr.  Charles  Reutlinger,  the  veteran 
Parisian  photographer.  It  will  be  gathered  from  the  description  that  it  has 
many  disadvantages.  (Fig.  79.)  The  studio  is  exposed  to  the  north,  is  quite 

therefore,  a  low  glass-house  is  preferable,  and  celebrated  photographers,  like  Reutlinger, 
Salomon,  etc.,  have  glass-houses  of  from  10  to  12  feet  high. 

Pictures  taken  in  high  glass-houses  appear,  very  often,  from  head  to  feet,  flat  and 
monotonous,  unless  particular  precaution  has  been  exercised. 

The  practical  conclusions  which  can  be  drawn  from  the  above,  go  still  further :  I  can 
prove  -that  an  excessively  long  glass-house  is  of  as  little  use  as  an  excessively  high  one. 

I  start  with  an  example.  The  glass-house  of  my  friends,  Loescher  &  Petsch,  is  32 
feet  long  by  16  feet  wide,  with  north  front.  (Fig.  78.) 

Suppose  5  feet  from  the  glass  side  and  4  from  the  back,  we  place  a  person  a ;  the 
whole  side  is  open,  except  immediately  alongside  and  behind  the  person  / '  g;  we  will 
have  a  criterion  of  the  amount  of  light,  by  drawing  the  lines 
ag  and  a  h,  that  is,  we  construct  the  angle  of  light  g  a  h. 

If  the  glass-house,  instead  of  being  32  feet  long,  were  only 
24  feet  long,  i.  e.,  if  it  stopped  at  i,  then  the  amount  of  light 
would  be  determined  by  the  angle  i  a  g,  all  other  circumstances 
being  equal.  The  figure  shows  that  the  difference  between  the 
angles  lag  and  hag  is  small,  or,  what  amounts  to  the  same, 
that  in  this  particular  instance  the  lengthening  of  the  room 
by  8  feet  (the  piece  i  h}  is  of  no  advantage. 

If  we  imagine  now,  instead  of  the  long  glass  side  g  h,  another 
inclined  one,  kg,  of  only  8  feet  length,  the  angle  of  light  bag 
will  then  be  exactly  as  large  as  the  angle  hag,  or,  which  is  the 
same,  the  small  side  of  only  8  feet  will  give  as  much  light  to  the 
person  at  a,  as  the  long  side  of  28  feet. 

According  to  the  above,  the  long  side  of  28  feet  can  be  re- 
placed by  one  of  8  feet,  when  we  propose  to  take  the  portrait  of 
a  person  at  a.  In  the  same  manner  I  can  replace  the  long  glass 
roof  of  28  feet  by  an  inclined  one  of  8  feet  length. 

When  I  construct  a  glass-house  now  with  inclined  sides  and 

an  analogously  inclined  roof,  I  will  obtain  a  room  which,  to  the  taking  of  single  portraits, 
is  as  well  adapted  as  one  of  28  feet  in  length.  Such  a  glass-house  would  have  the  form 
represented  in  Fig.  80. 

I  do  not  mean  to  say,  however,  that  it  follows  from  the  above  that  the  construction 
with  inclined  sides  is  perfect.  On  the  contrary,  such  a  construction  has  some  serious 
drawbacks. 


GLASS-HOUSE    CONSTRUCTION. 


85 


plain,  and  is  30  feet  long  by  15  feet  wide;  but  of  the  length  only  16  feet 
are  of  glass ;  the  balance  is  a  small  room,  which  was  added  to  give  it  more 


FIG.  79. 


length.  The  glass  side  is  9  feet  high,  and  is  divided  into  three  parts.  1st. 
The  lower  part,  G,  is  a  wall  1J  feet  high.  2d.  The  middle  part,  F,  4  feet 
high,  is  of  stained  glass.  3d.  The  top,  E9  4J  feet,  is  of  common  white  glass. 

A  glass-house  like  the  one  described  in  Fig.  80,  with  sides  inclined,  would  do  very  well 
for  taking  single  portraits.  The  side  wall  should  face  north.  But  the  case  is  entirely 
different  when  we  wish  to  use  the  whole  space  for  taking  groups. 


FIG.  80. 


FIG.  81. 


f 

OH 

j 

^vfc 

o     > 

t 

en        V^X^***  —  "          ""   "" 

Suppose  we  wish  to  take  the  portrait  of  a  person  at  b,  Fig.  81,  in  an  ordinary  glass- 
house, twice  as  far  distant  from  the  glass  side,  as  a ;  by  measuring  now  the  angle  of 
light,  and  drawing  the  lines  b  h  and  b  k,  we  will  find  the  quantity  of  light  which  the 
sides  g  h  and  g  k  will  give  at  the  angles  h  b  g  and  kbg\  it  is  evident  that  the  angle  h  b  g 
is  much  larger  than  k  b  g,  and  consequently  the  illumination  of  a  point  distant  from  the 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


The  whole  roof  of  this  is  made  of  stained  glass.  To  guard  against  the  strong 
rays  of  the  sun  in  summer,  a  blind  over  the  whole  length  of  the  roof  is  used 
which  has  a  height  of  about  5  feet,  and  is  managed  by  a  crank  inside  of  the 
studio.  Besides,  there  are  inside  six  different  screens  or  curtains  of  blue  calico, 
to  shade  the  light  from  the  top,  and  also  to  guard  against  the  reflection  of  the 
sun  from  the  houses  opposite.  There  is  only  one  side  where  one  can  sit  the 
model ;  and  it  is  only  when  they  sit  for  small  vignettes  that  one  can  place  them 
on  the  other  side,  on  account  of  the  shortness  of  the  studio.  This  accounts  for 
all  Mr.  Keutlinger's  productions  being  lighted  from  the  same  side,  which  is 
very  troublesome  with  a  great  many  subjects.  Another  inconvenience  is  the 
small  width.  For  this  reason,  he  is  unable  to  have  his  backgrounds  on  frames, 
as  is  usually  the  practice.  He  uses  rollers,  which  are  let  up  and  down,  with 
balustrades,  chimneys,  columns,  etc.,  as  auxiliaries.  We  see  by  this,  that  the 
greatest  caution  and  order  in  the  small  remaining  space  is  necessary  for  the 
posing  of  persons,  and  many  outsiders  are  astonished  that  so  many  pictures  are 
made  in  such  a  small,  insignificant  room. 

In  Amsterdam,  Mr.  P.  A.  Mottu  has  erected  an  elaborate  studio,  supplied 
with  all  manner  of  inside  screens,  shutters,  and  blinds.  (Fig.  83.)  This  is  a 
double  studio,  again  divided,  when  in  use,  by  heavy  drapery.  The  plan  of 

inclined  side,  kg,  in  a  glass-house  facing  north,  is  much  more  favorable  than  in  the 
smaller  one,  which  gave  for  a,  for  a  single  portrait,  the  same  amount  of  light  as  the 
larger  one.  In  the  small  glass-house  we  are  confined  to  the  small  space  in  the  neighbor- 
hood of  the  glass  side,  while,  with  a  glass-house  the  front  of  which  faces  north,  we  can 

spread  in  depth,  and  have  the  advantage  which 
it  offers  for  taking  groups  and  making  artistic 
arrangements. 

Artists  will  always  give  the  preference  to  a 
north-front  glass-house. 

I  might  carry  out  the  above  still  further,  but 
I  think  the  explanation  of  the  principles  of 
illumination  will  be  sufficient. 

To  anyone  who  wishes  to  construct  a  north- 
front  glass-house  for  small  work,  I  would 
recommend  the  annexed  plan  (Fig.  82).  It 
represents  a  space  of  32  feet  long ;  the  middle, 

a  a,  is  glazed  for  a  space  of  16  feet;  depth,  16  feet;  height,  front,  10,  and  back,  15  feet, 
The  space  b  b  is  dark,  and  serves  for  moving  back  the  apparatus.  If  only  one  person  is 
to  be  illuminated  from  one  side,  as  Reutlinger  does,  a  space  can  be  partitioned  off  and 
used  for  other  purposes. — DR.  H.  W.  VOGEL. 


FIG.  82. 


t 

I 

1  « 

&                     n. 

4, 

**~     B 

•*»•*-               ie*                  —  »<- 

a'  -• 

GLASS-HOUSE    CONSTRUCTION 


87 


curtaining  and  arranging  the  inside  blinds  may  be  useful,  though  perhaps 
unnecessarily  elaborate. 


FIG.  83. 


FIG.  84. 


27.  The  most  exasperating  light  of  any  is. the  one  with  only  a  south  expo- 
sure.    The  sun  reaches  it  nearly  all  day  during  the  summer,  and  in  the  winter 

27.  I  have  worked  a  light,  not  quite  south,  but  so  situated  that  it  received  the  sun  all 
the  forepart  of  the  day.  From  my  experience  with  that  light  I  would  suggest  opaque 
curtains  under  white  muslin,  so  as  to  exclude  the  light  from  such  portion  as  may  be 
desired,  by  arranging  the  opaque  curtains  so 
as  to  open  or  close  different  parts  of  the  light. 

Any  drab  or  slate-colored  material  may  be 
used,  and  can  be  put  up  conveniently  and  at 
little  expense,  by  running  them  on  wires,  later- 
ally across  the  light.  The  sitter  must  be  placed 
in  the  light,  not  away  to  one  side  of  it. 

The  following  amendments  to  the  diagram 
(Fig.  84)  will  illustrate  the  best  method  of 
working.  Place  the  sitter  on  the  lines  a  orax, 
as  may  be  desirable  for  the  sitter,  with  the 
camera  at  b  or  b' ',  and  arrange  the  curtains  by 
the  directions  given  in  Bigelow's  Album,  for 
such  effect  as  you  wish  to  produce. 

Placing  the  sitter  fronting  the  light,  or  the 

sitter  and  camera  on  a  line  with  the  light,  cannot,  in  the  nature  of  things,  produce  good 
work  under  any  light.     Notice  a  view  made  with  the  sun  directly  behind  the  camera  and 


88 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


it  is  available  for  fewer  hours  than  any  other.  Avoid  it,  if  possible.  The 
drawings  and  notes  will  be  useful.  In  a  south  light  the  sitters  are  usually 
placed  at  a  or  a,  and  the  camera  at  d  or  d.  A  standing  figure  or  group  gener- 


FIG.  85. 


FIG.  86. 


ally  to  the  right.     At  b  place  the  sitter  for  a  shadow  or  Rembrandt  effect,  c 
being  a  Bigelow  background. 

I  also  add  a  horizontal  view.  (Fig.  86.)     The  difficulties  are  apparent. 


see  how  flat  and  insipid  it  is.  Notice  another  of  the  same  subject,  with  the  sun  at  right 
angles,  or  nearly  so,  with  the  view,  and  see  the  boldness  and  relief.  This  is  just  as  appli- 
cable to  portraiture  as  to  landscape  photography.  If  we  would  have  form  and  modelling, 
the  light  must  fall  around  the  sitter,  and  come  mainly  from  one  side. — JOHIST  L.  GIHON. 

I  have  concluded  to  give  my  experience  of  running  a  south  light.  My  top-light  is 
about  10  x  15,  side-light  about  8  x  15,  with  a  pitch  of  about  two  feet  from  the  highest 
part  of  the  top-light  to  the  top  of  the  side-light.  I  have  six  curtains  on  my  top-light, 
divided  in  the  centre,  so  that  I  can  slide  them  either  way,  as  they  run  on  wires,  without 
being  held  fast  at  either  end.  My  side-light  has  ten  shutters,  which  can  be  opened 
separately  or  all  together,  if  the  light  is  weak ;  and,  lastly,  my  glass  is  pretty  heavily 
blue- frosted. 

I  place  the  model  under  the  centre  of  the  skylight  and  draw  down  all  the  curtains  and 
shut  off  the  side-light.  Now  there  is  no  light  at  all  on  the  subject  or  at  least  a  very 
subdued  one.  I  then  open  my  last  side-shutter,  which  is  about  four  feet  from  and  in 
the  rear  of  the  sitter,  and  light  up  the  side  of  the  head  and  top  of  the  forehead,  and  this 
manner  of  lighting  also  throws  a  very  soft  effect  back  of  the  head,  giving  detail  to  the 
hair  and  rounding  the  figure  up.  Now  we  find  that  the  shadows  are  a  little  too  strong 
on  the  other  side  of  the  face,  and  to  remedy  this  I  draw  back  the  left  half  of  my  first  or 
second  curtain  (I  am  now  supposed  to  be  facing  the  sitter),  according  to  the  time  of  day, 
enough  to  give  the  desired  effect,  and  use  no  side  screen  (which  I  consider  spoils  the 
effect  of  every  picture  in  which  it  is  used). 

This  way  of  lighting,  which  was  new  to  me,  I  found  out  by  accident,  by  being  c  om- 
pelled  to  make  a  sitting  late  in  the  evening.  I  opened  the  back  side-light  in  order  to 


GLASS-HOUSE    CONSTRUCTION. 


89 


FIG  67- 


28.  Allusion  has  been  made  to  studios  in  Europe  which  are  built  upon  the 
roofs  of  larger  buildings.  Fig.  87  is  a  plan  made  from  such  a  studio.  One 
great  advantage  it  has,  namely,  an 
occasional  overflow  cannot  dam- 
age the  property  below.  More- 
over, it  is  warm  in  winter,  cool 
in  summer ;  neither  morning  nor 
evening  sun  shall  annoy ;  there  is 
equality  of  light,  and  that  light 
most  easily  managed ;  it  is  easily 
ventilated,  and  on  the  glass  dust 
does  not  accumulate  more  than  on 
common  windows,  and  is  remov- 
able with  no  greater  difficulty. 

The  source  of  light  is  entirely 
from  the  front,  and  the  top-front  light  and  the  side  lights  are  amply  supplied 
by  reflection  from  the  roof  and  sides  sloping  respectively  upward  and  outward. 
The  angle  here  adopted  may  be  40°  or  50°. 

shorten  the  exposure,  and  got  a  very  good  result,  since  which  time  I  have  practised 
it. — C.  S.  McCoRMiCK. 
28.  Mr.  Luckhardt's  establishment  is  a  model  one.     It  is  situated  on  the  roof  or  ter- 

FIG.  88. 


A  F,  glass-house  ;  A  JJ  U  V,  swing  window ;  L  M  P  JVand  T, 
French  windows  ;  H I L  K,  tunnel ;  SR  dark-room. 


race  of  the  Grand  Hotel,  Vienna.     His  reception,  dressing,  exhibition,  finishing,  and 
delivery  rooms  are  all  on  one  floor,  and  over  these  the  skylight,  dark-room,  printing,  and 


90 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


With  a  window  eight  feet  by  ten,  facing  the  north,  and  a  model  opposite  it 
at  the  distance  of  thirteen  or  fourteen  feet,  the  lighting  is  good.  Add  the 
sloping  walls  and  ceiling,  with  their  reflecting  surfaces,  and  you  have  a  soft  light. 

solar-camera  departments  are  conveniently  arranged,  and  supplied  with  every  necessary 
thing  to  make  the  best  of  results.  The  assortment  of  furniture  and  backgrounds  is  lavish 
and  elegant.  The  drawings  (Figs.  88  and  89)  will  bring  it  more  plainly  to  mind. 

The  first  one  is  an  exterior  view.  It  represents  it  as  standing  on  the  ground,  while  in 
reality  it  is  built  upon  the  solid  marble  roof  of  a  hotel,  the  other  rooms  mentioned  being 
underneath  in  the  hotel  building.  • 

JTis  the  entrance  from  the  roof"  to  the  dark-room ;  B  is  the  top-light,  which  is  sunk 
below  the  angle  of  the  roof  DE\  and  C  is  the  side-light,  both  of  which  face  the  north. 
It  reminded  me  more  of  Messrs.  Trask  &  Bacon's  Philadelphia  light  than  any  I  have 
seen.  MN  is  a  "  sunshade,"  erected  to  protect  the  skylight  from  the  southern  sun. 
Separate  from  this  on  the  roof  are  the  printing  and  solar-camera  rooms. 


FIG.  89. 


FIG.  90. 


A 
I 

--u  &U  

J 

i 

i 

i 

• 

1 

i 

• 

<N 

v  > 

j1 

5 

«~—E46        * 

I. 

_ 

| 

"***  

V 

^Iw 

! 

! 

£  i--A2«?' 

-?-   i_  J 

V 

1><) 


The  next  figure  (Fig.  89)  gives  us  the  exact  ground-plan  of  the  whole,  and  the  third 
figure  (Fig.  90)  a  sectipnal  view  of  the  skylight  proper. 

The  dimensions  are  given  by  the  figures  in  Austrian  feet  and  inches,  and  the  Austrian 
foot  is  about  three-eights  of  an  inch  longer  than  ours.  Where  two  commas  are  over  the 
figure  it  means  inches,  and  where  one  only  is  used,  feet  are  meant. 

Mr.  Luckhardt  usually  works  an  open  light,  and  from  both  ends  of  the  room,  east  and 
west. 

He  truly  said,  "The  skylight  construction  is  not  the  thing.  It  is  the  good  quality  of 
the  light  from  heaven  itself.  Give  me  that  and  I  will  do  all  the  rest,  even  without  any 
studio.  If  the  light  is  not  good,  I  dismiss  my  sitters,  and  wait  until  it  is  good  ;  or,  if  they 
cannot  wait,  I  ask  them  to  come  again.  If  they  cannot  do  either,  then  I  request  them  to 
go  to  another  photographer,  as  I  will  not  willingly  make  a  bad  picture.  With  me  it  is 
all  a  matter  of  feeling,  and  I  cannot  work  without  it.  One  cannot  impart  this  to  another, 
or  hardly  describe  it." 


GLASS-HOUSE    CONSTRUCTION. 


91 


FIG  91. 


29.  I  once  saw  a  man  make  very  good  work  in  what  he  called  his 
"  Curiosity  Skylight."  And  it  was  a  "  curiosity. "  The  diagram  (Fig.  91) 
will  prove  it. 

The  top-light  was  originally  made  to  light  the  store  below,  a  a  are  the 
lights,  six  in  number  (half-inch  thick  glass),  3x4  feet,  arranged  as  indicated 
by  the  dotted  lines.  B  the  end,  and  b  b 
the  sides  of  the  opening  in  the  roof,  4 
feet  9  inches  by  1 2  feet ;  and  c,  screens 
of  blue  paper  which  slide  under  the 
ceiling,  d,  when  not  in  use ;  e  e  are  the 
backgrounds  in  position.  The  side- 
walls  are  white-coated,  and  act  as  side 
lights. 

By  placing  the  sitters  near  the  middle 
of  the  room,  strong  top-light  is  ob- 
tained ;  and  by  placing  them  near  the 
white  wall  strong  side-light.  The  back- 
grounds usually  stand  about  six  feet 
from  under  the  light ;  and  to  darken 
them  run  them  back  from  the  sitter. 
He  arranged  sittings  on  all  sides  of  the  light  occasionally,  but  usually  on  the 
southeast  or  southwest  side.  By  becoming  familiar  with  the  light  he  became 
master  of  it.  The  glass  was  half  an  inch  thick,  ribbed. 

Those  who  think  their  skylights  are  not  good  should  study  the  nature  of 
them,  and  in  nine  cases  out  of  ten  they  will  find  they  have  too  much  light,  or 
are  making  sittings  on  the  wrong  side  of  the  room.  If  you  cannot  direct  the 
light  the  way  you  wish,  watch  which  way  it  will  go,  and  by  a  little  judicious 
management  of  your  screens,  your  worst  enemy,  light,  becomes  your  servant 
and  friend. 

I  have  seen  many  worse  glass  houses  than  this.  I  have  tried  to  show  a 
variety  of  forms  for  study,  for  I  am  well  aware  how  much  dodging  is  often 
required  to  get  even  a  tolerable  studio. 

29.  My  method  of  taking  children's  photographs  is  very  simple ;  the  first  and  most 
essential  requisite  being  patience  coupled  with  good  humor,  or  at  least  a  seeming  good 
humor.  Add  to  these  prerequisites,  good  assistants,  good  lights,  good  chemicals,  and 
good  artists,  and  you  have  my  secret,  if  such  you  choose  to  term  it,  of  taking  pictures  of 
children.  One  of  the  studios  which  I  use  has  a  south  light,  and  is  peculiarly  adapted  to 


92  WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

30.  So  much  now  for  the  elevation.  As  further  help  I  add  two  ground- 
plans,  thus  providing  suggestions  for  even  the  humblest  of  our  fraternity. 

The  first  (Fig.  93)  is  of  a  studio  in  Texas,  40  feet  long  by  20  feet  wide.  The 
side-light  comes  within  3  feet  of  the  floor.  The  lower  side  of  the  skylight 
rests  upon  the  side-light,  and  the  upper  side  is  raised  5  feet  higher,  and  the 
sides  boxed  up  and  tinned  the  same  as  the  roof. 

the  taking  of  children's  pictures,  it  being  covered  with  fluted  glass,  and  well  supplied  with 
screens,  which  enable  me  to  throw  on  or  shut  off  the  light  almost  instantaneously  in  any 
quantity  to  suit  the  subject.  I  have,  with  the  assistance  of  these  essentials,  taken  more 


FIG 


than  twenty  children  in  one  day,  beside  other  work  as  it  chanced  to  come  in.  I  make  it 
a  rule  to  have  two  plates  always  ready  when  taking  children,  which  enable  me  to  make 
four  impressions  of  the  child,  one  of  which  is  almost  sure  to  be  a  goood  one.  This  is  my 
simple  way  of  taking  pictures  of  the  little  ones,  and  good  artists  complete  the  work  so 
simply  begun. — JOHN  A.  SCHOLTEN. 

30.  The  construction  of  the  roof  of  a  glass-house  is  a  matter  that  will  bear,  and  should 
get,  very  serious  consideration. 

The  form  of  sash-bar  I  give  below  is  rather  different  from  that  in  common  use,  and 
consists  of  two  pieces.  Here  are  sections  of  them.  Fig.  94. 

The  object  of  the  grooves  in  B  is  to  catch  and  convey  outside  any  leakage  at  the  edges 
of  the  panes ;  and  is  copied  from  the  Photographic  News  Year- Book. 


GLASS-HOUSE    CONSTRUCTION. 


93 


A  is  the  reception-room,  12  by  20  feet.  B  is  the  studio,  13  by  28  feet.  A 
double  door  leading  into  it  can  be  thrown  open,  and  the  camera  run  back  into 
the  reception-room  a  distance  of  40  feet,  which  is  a  great  advantage  when 


FIG.  93. 

s         B 

r® 

1                                                           K 

-K  f 

(1  STOVE 

'  C                  D             /  E    K 

o     p 

;  F  s 

L 

JK 

A 

SKY   LIGHT 
\                              7  2  X  13 

SIUE    LIGHT 
13  X? 

H 

N 

w 


making  groups.  C  is  the  dressing-room,  6  by  8J  feet.  Z>  the  printing-room, 
11  by  6  feet.  G  is  a  long  window  for  printing  in.  The  frames  are  placed  on 
a  shelf  just  outside.  E  the  dark-room  for  paper,  negatives,  etc.  F  is  the 

Where  the  ordinary  form  of  sash  is  in  use,  a  strip  of  wood  shaped  thus,  and  screwed 
to  the  underside  of  the  bar,  will  be  found  a  very  useful  addition.  The  plan,  however,  I 
have  to  suggest,  is  the  employment  of  a  strip  of  soft  India-rubber  cord 
in  place  of  putty  on  the  outside  of  the  glass,  which  is  brought  closely 
down  upon  it  by  means  of  the  slip  of  wood  (or,  preferably,  iron)  shown 
in  the  cut,  marked  A.  The  glass  having  been  bedded  as  usual  in 
putty,  A  is  screwed  down,  and  with  the  India-rubber  forms  an  imper- 
meable joint,  which,  unlike  the  putty,  will  yield  to  the  shaking  of  the 
roof  in  windy  weather,  but  it  will  not  allow  the  passage  of  any  water. 
Another  advantage  consists  in  the  fact  that  if  the  glass  be  also  bedded 
on  rubber,  they  can,  by  merely  unscrewing  A,  be  lifted  out,  without  the 
very  serious  risk  of  breakage  that  attends  the  removal  of  glass  fastened 
in  with  putty;  and  photographers  would  then  be  able  to  arrange  with 
glass  merchants  for  the  yearly  renewal  of  the  glass  in  their  studios  at  a 
low  figure ;  no  unimportant  point,  when  the  rapid  yellowing  of  common 
glass  is  considered.  When  large  panes  are  used,  leakage  will  also  take  place  at  the  lap- 
joints,  partly  by  capillary  attraction,  but  mostly  from  the  bending  of  glass  in  heavy 


94  WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

negative  dark-rooni;  kkk  are  shelves  18  inches  wide,  3  feet  from  the  floor; 
above  these  are  several  other  shelves  for  storage,  etc.  S  is  the  sink,  with  a 
pipe  to  carry  off  the  water.  Over  this  develop,  fix,  and  put  the  developiug- 
bottles  on  the  little  shelf  to  the  right.  T  is  a  cistern  outside,  with  lead  pipe  to 
lead  the  water  into  the  room.  0  is  a  14  by  17  inch  bath.  The  shelf  back  of 
this  is  24  inches  wide,  giving  plenty  of  room  for  plate-holders  back  of  it. 
Ill  are  little  yellow  windows,  of  two  thicknesses  of  orange  glass.  L  shelves, 
to  the  ceiling,  for  different  sized  negatives. 

The  outside  blinds  recommended  by  Mr.  Trask,  further  on,  are  used  here. 

For  those  whose  means  are  greater  the  ground-plan  of  Mr,  Henry  Kocher's 
Chicago  studio  will  be  found  useful.  It  has  about  all  the  useful  conveniences. 

31.  Plan  of  basement  floor :  Kooms  8  feet  high.  N,  north;  8,  south;  E, 
east ;  W,  west.  A,  entrance  and  hall.  B,  Mr.  Rocher's  private  parlor.  C, 
artist's  room,  c,  artist's  seat  and  easel.  D  D,  retoucher's  stands.  E,  mounting 

winds.  To  prevent  this,  a  thin  piece  of  elastic  might  be  inserted  between  the  panes, 
and  supplemented  by  the  use  of  a  strip  of  wood  placed  on  the  top  of  the  iron  rods  that 
run  along  under  the  laps  inside  the  house.  As  these  joints  soon  get  filled  with  dirt,  the 
employment  of  the  wood  would  not  occasion  any  loss  of  light,  and  would  strengthen  the 
glass  \7ery  materially,  thus  allowing  the  use  of  large  panes.  There  are  many  modifica- 
tions of  the  above  plan  that  might  be  adopted,  but  I  will  venture  to  assert  that  the 
principle  is  the  right  one. 

To  those  who  print  outside  with  glass-fronted  frames,  the  adoption  of  this  plan  will 
save  a  good  many  prints  in  wet  weather,  and  possibly  some  negatives,  as  I  have  seen 
such  a  thing  as  the  paper  sticking  to  negatives,  and  fetching  away  the  film  with  it  when 
pulled  off. — LONDON  STONE. 

31.  I  have  always  been  bothered  with  leaky  skylights,  until  a  short  time  ago,  when  I 
determined  to  put  a  stop  to  it.     I  tore  out  my  old  light  and  made  a  frame  out  of  pine 
t  pieces  Ijx3  inches  for  the  centre  strips,  and  the  edges  are  con- 

siderably heavier.  And,  in  place  of  making  the  sash  as  is  usual, 
I  cut  a  groove  on  each  side  of  the  centre  strip,  about  £  inch  from 
the  top,  as  seen  in  Fig.  95,  and  put  pieces  of  tin  in,  shaped  as  in 
Fig.  96,  to  prevent  the  glass  from  slipping  down ;  then  I  mixed 
my  putty,  about  one-half  white  lead,  and  puttied  the  glass  in  care- 
fully, then  gave  the  outside  two  heavy  coats  of  white-lead  paint, 
SL?  and  I  have  been  well  rewarded  for  the  trouble,  as  it  is  as  light  as 

can  be. 

One  great  mistake  in  putting  in  lights  is,  that  the  sash  is  not  heavy  enough,  so  that 
the  wind  shakes  the  putty  loose.  With  this,  if  the  putty  all  comes  out  the  glass  cannot. 

— A.  E.  TURNBULL. 


GLASS-HOUSE    CONSTRUCTION 


95 


tables.     F,  furnace.      G  G,  shelves.     H,  framing  table.     J,  dumb-waiter.    Ky 
toning  and  fixing  table.    L,  sink.  M  N,  washing  tanks.   0,  vault  for  tubes,  etc. 


Fid.  98. 
N 


\a 


20  FT 


9FT. 


Plan  of  studio  for  first  floor:  Size  of  floor,  19  x  36  feet,  and  11  feet  high. 
P,  dressing-room.  Q  Q  Q,  heat  registers.  Ry  dark-room,  S,  dumb-waiter. 
T,  lead-lined  sink,  with  yellow  window  in  front  of  it.  U  U,  tables.  T7',  shelves, 
for  negatives  from  stereo  size  to  17  x  20.  Tf7,  silver  baths  of  sizes  marked. 
X,  drawers.  F,  printing-room.  The  main  space  represents  the  studio.  North 
light,  20  feet  wide  by  18  long;  side-light,  20x8  feet  high.  Inclination  40 
degrees. 


96 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


32.  At  the  convention  of  the  National  Photographic  Association,  held  in 
Philadelphia  in  1871,  a  model  for  a  skylight  was  exhibited,  of  which  the 
accompanying  cut  (Fig.  99)  is  a  representation.  It  was  partly  suggested  by  a 


FIG.  99. 


hailstorm.  A  A,  the  framework  of  the  top  light,  all  glazed,  which  is  made  so 
that  it  can  be  used  as  shown  in  the  cut  (top  inclination  and  side  light  to  the 

32.  To  prevent  leaking,  I  use  an  iron  sash  made  of  the  shape  of  the  little  diagram 
annexed  (Fig.  100),  the  hollows  of  which  I  fill  with  a  thick  paste  made  of  white  and  red 
lead  and  copal  varnish.     The  glass  is  then  imbedded  in  the  paste,  and  is 
FIG.  100.       perfectly  water-tight  at  the  sides.     The  sash  is  made  for  both  inside  and 
outside  use.     To  prevent  water  entering  the  room,  where  the  lights  over- 
lap, get  some  pieces  of  sheet-lead,  and  run  them  through  the  roller-press 
to  make  them  very  thin.     They  are, then  cut  into  strips,  say  half  an  inch 
wide,  and  bent  hook-shaped,  -  — .  like  the  figure.    They  are  placed 

between  the  glass  in  a  manner  easily  understood,  where  they  overlap  and  entirely 
prevent  capillary  attraction  by  allowing  air  to  pass  between  the  glass. — ELWOOD 
GARRETT. 


GLASS-HOUSE    CONSTRUCTION.  97 

north) ;  B  B,  the  frame  of  the  side  light,  all  glazed ;  C  C,  the  frame  of  the 
top  blinds;  D  D  D  D,  the  upright  supporting  the  frame  C  C]  E  E,  top  blind 
frames,  covered  with  canvas ;  F  F,  ditto,  uncovered ;  G,  a  glazed  top  sash, 
without  inside  curtain  or  blind ;  H  Hy  wooden  sliding  frames,  covered  with 
tissue-paper  ;  7,  a  spring-roller  curtain ;  J,  movable-top  blind  frame,  uncovered ; 
K,  ditto,  covered ;  L  L,  ditto,  for  side  light ;  M,  same  as  L,  uncovered ; 
JV  N  N  N,  side  frames,  uncovered,  and  outside  sash  showing  through  '000, 
side  sash,  glazed,  and  exposed  inside,  and  may  be  covered  by  either  of  the 
arrangements,  H,  J,  or  /.  For  coolness  in  summer  and  warmth  in  winter  the 
outside  blinds  are  helpful,  and  may  indeed  also  be  used  to  modify  the  light. 
•  These  arrangements  for  shades  and  blinds  are  not  all  for  use  on  the  same 
studio,  but  are  given  here  that  parties  may  choose  whichever  is  best  adapted  to 
their  individual  requirements. 

This  style  of  skylight  is  probably  more  generally  used,  in  modified  forms, 
than  any  other,  and,  in  about  the  proportions  here  represented,  has  been  worked 
with  uniform  success.  The  size  of  the  light  must  be  governed  by  the  size  of 
the  room  it  is  expected  to  illuminate.  A  room  12  feet  wide  will  not  require 
the  top  light  more  than  8  or  9  feet  up  the  roof;  while  along  the  room  it  should 
be  not  less  than  10  feet  nor  more  than  15  feet,  and  placed  in  the  centre.  The 
side  light  should  be  not  over  10  feet  from  the  floor,  where  it  intersects  the  top 
light,  and,  for  a  small  studio  8  feet  would  be  better.  The  bottom  of  the  side 
light  should  be  about  2  feet  from  the  floor. 

Particular  attention  is  drawn  to  the  outside  construction — to  the  shades  for 
protection  in  storms  of  rain  and  hail,  to  the  sash  bars,  and  to  the  glazing.  The 
reader  is  also  referred  to  Lesson  J,  in  Wilson's  Photographies. 

33.  Many  itinerant  photographers  use  a  car,  on  wheels,  or  a  tent.     For 

33.  On  the  new  atelier  of  Loescher  &  Petsch,  in  Berlin,  to  the  supports  of  the  roof 
corner-irons,  e  (Fig.  101),  f  xf  inch,  are  riveted,  and  these  carry  the  frames  for  inside 
blinds.  The  irons  have  three  grooves,  in  each  of  which  a  frame  can  be  moved  without 

FIG.  101.  FIG.  102. 


touching  the  other  one.  Placed  side  by  side,  they  cover  the  glazed  three-quarters  of  the 
roof  completely ;  placed  one  above  the  other,  and  pushed  under  the  covered  quarter  of 
the  roof,  the  glazed  part  is  unobstructed.  See  Figs.  101  and  102. 


98 


WILSON'S    QUARTEK    CENTURY    IN    PHOTOGRAPHY. 


plans  for  building  a  photographic  car  I  am  indebted  to  Mr.  C.  U.  Stevens 
(Fig.  102.)     First  the  sills  are  laid  and  bolted.     There  are  five.      The  two 


FIG.  103. 


22    FT. 


which  are  bolted  at  the  bolsters  are  2x6,  the  other  three  are  2x4.     Next  put 
in  cross  braces,  made  of  one-inch  boards,  ripped  two  inches  wide.     The  floor  is 

Fig.  104  will  show  this  arrangement — cross  section.  H  is  the  rear  wall ;  h  a  wooden 
covering  for  the  roof;  r  r/r///  are  the  frames  which  move  in  the  guides  as  shown  in  Figs. 
101  and  102.  Each  frame  has  two  small  hooks,  x'  x"  x"',  etc.  The  frames  are  moved 
by  cords,  which  at  H  and  V  pass  over  rollers,  and  which  at  V  are  fastened  to  the 
first  frame.  In  admitting  light,  r'  will  move  backward;  first  the  hook  x'  will  catch  the 
corresponding  hook  x"  of  frame  r',  and  take  the  second  frame  along,  and  so  all  the 

FIG.  104. 


n 


frames  will  be  caught  in  succession.  Friction  is  partially  overcome  by  strips  of  wood, 
h,  Fig.  101,  which  are  covered  with  plumbago,  and  placed  under  the  frames ;  so  also  are 
the  hooks  Ft  Fig.  101,  covered  with  felt  to  avoid  jarring. 

The  movement  of  the  frames  is  easy  and  certain,  and  the  exclusion  of  the  light 
complete. 

The  side  light  is  regulated  in  a  similar  manner. — DR.  H.  W.  VOGEL. 


GLASS-HOUSE    CONSTRUCTION.  99 

then  laid.  Next  put  up  a  frame,  made  of  the  same  stuff,  like  the  diagram. 
Where  the  strips  cross  they  are  halved,  and  a  screw  put  in.  They  are  also 
screwed  at  the  top  and  bottom.  The  roof  is  bowed  with  a  pitch  of  8  inches. 
The  frame  is  then  covered  with  a  felt-paper  and  half-inch  sliding  running  up 
and  down,  and  matched.  Where  the  boards  cross  the  frame  there  are  two 
screws  in  each  crossing.  "The  car  is  smooth  on  the  outside,  which  gives  a 
better  chance  for  fancy  painting.  The  roof  is  covered  with  half-inch  stuff; 
then  a  layer  of  tarred  felt-paper,  then  a  layer  of  half-inch  stuff  on  that  again, 
and  well  painted  with  mineral  paint,  both  between  the  joints  and  between  the 
paper  and  outside  covering,  and  then  four  coats  of  the  same  on  the  outside. 
There  are  two  side  windows,  north  and  south,  and  skylight  facing  north.  The 
side  windows  are  two  common  sash  windows,  side  by  side.  The  glass  is  8  x  14. 
The  skylight  is  5  J  x  7  feet.  The  rear  is  raised,  when  in  position,  4J  feet. 
There  are  two  doors  for  entrance  on  each  side ;  also  a  small  door  in  the  forward 
end,  to  accommodate  the  driver  when  moving.  The  truck-wheels  are  30  inches 
in  diameter.  The  forward  ones  2  feet  from  the  end,  the  back  ones  4J  feet  from 
the  rear  end.  The  skylight  is  3  feet  from  the  rear  end,  and  pitches  to  the 
side.  The  side  windows  are  3J  feet  from  the  rear  end  of  the  car,  and  1  foot 
from  the  floor.  It  is  6  feet  from  the  side  light  to  the  door.  The  dark-room 
is  3  x  4J  feet,  and  the  work-room  4  J  x  5  feet.  The  car  is  22  feet  long,  8  feet 
wide,  7  feet  high  at  the  eaves.  Four  thousand  screws  are  needed  to  fasten  it 
together.  It  is  lined  inside  with  quarter-inch  stuff,  and  papered  with  wall- 
paper or  Lincrusta  Walton.  It  should  be  covered  overhead  with  the  same,  and 
painted  drab. 

34.  In  the  southern  sections  a  tent  will  be  found  cooler  and  more  portable. 

34.  An  apparatus  for  keeping  the  operating-room  cool  in  summer,  warm  in  winter, 
and  always  protected  from  hail,  was  devised  by  Mr.  L.  M.  Whitney.  It  consists  of  blinds 
or  shutters  so  arranged  that  one  can  from  the  operating-room  open  or  shut  them  in  a 
very  few  minutes.  When  not  using  the  light  they  can  be  drawn,  keeping  the  room  cool. 
The  slats  are  fastened  together  with  webbing,  one  strip  over  and  one  under,  making  a 
joint  that  will  fold  either  way  without  any  trouble;  will  pack  themselves  away  as 
perfectly  as  seen  in  the  drawing  (Fig.  106).  The  box  they  fold  into  is  covered  up, 
keeping  them  dry  when  not  in  use.  Any  good  workman  can  apply  them  to  most  any 
skylight.  The  cords  pass  over  pulleys  down  into  the  room  on  both  sides ;  the  one  under 
the  slats,  when  drawn,  passes  over  the  roller  in  the  groove  made  for  it  to  draw  off 
the  blinds. 

For  a  light  say  12  x  16,  the  blind  should  be  divided  into  three  or  four  sections. 

It  is  made  entirely  of  pine ;  the  end  rails,  a  a,  are  1^x5  inches,  the  middle  ones  2x5, 


100 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


The  plan  below  was  made  from  one  in  actual  use.  (Fig.  105.)     The  following 
instructions  will  enable  others  to  construct  a  similar  one. 


FIG.  105. 


grooved  ^ 

irons  to  fit  the  angles,  and  screwed  on. 

FIG.  106. 


inch,  £  inch  from  top  of  rail  (Fig.  106),  and  fastened  to  the  skylight  with 
The  blinds,  b  b,  are  f  x  3  inches,  hinged  snugly 
together  with  heavy  boot-webbing,  c,  over  and 
under  alternately,  making  a  perfect  hinge,  the 
webbing  well  fastened  with  good-sized  tacks 
driven  obliquely  near  the  edge,  webbing  and  all 
well  painted ;  they  are  drawn  by  cords,  as  seen 
in  Fig.  106,  passing  through  the  pulleys,  //, 
which  are  screwed  to  the  strips  g  g,  under  the 
first  slat,  back  through  the  other  side,  over  a 
pulley  down  into  the  room  below.  The  strip 
h  h,  covers  the  space  over  the  pulleys  when 
down.  The  cord  that  draws  the  blinds  off  is 
fastened  in  the  strip  g,  passing  back  under  the 
blinds,  over  rollers  (which  are  four  inches  in  di- 
ameter at  ends  and  centre,  with  groove  for 
cord),  and  passing  down  into  the  room.  In 
drawing  them  back  they  fold  nearly  as  per- 


GLASS-HOUSE    CONSTRUCTION.  101 

The  frame  of  the  tent  is  made  of  spruce  pine  2x3  inches,  except  the  six 
posts  and  foot  pieces,  which  are  3x4  inches.  The  mortises  and  tenons  are 
cast-iron.  The  posts  are  screwed  into  the  mortises.  The  tent  is  pitched  with 
the  ends  east  and  west,  the  skylight  to  the  north.  The  dark-room  is  in  the 
west  end  of  the  tent,  in  two  apartments,  size  4J  x  8  feet,  by  6  feet  high.  It 
consists  of  a  frame  with  one  upright  post,  and  two  arms,  one  4J  and  the  other 
8J  feet,  making  the  length  and  width  of  the  room,  and  fastened  to  the  posts 
with  strap  hinges.  On  the  end  of  each  arm  is  a  hook,  which  fastens  to  an  eye 
in  the  plate.  The  frame  is  covered  with  double  brown  Canton  flannel. 

The  tent  frame  is  covered  with  twelve-ounce  canvas,  lined  with  brown 
Canton  flannel  to  exclude  the  light.  Over  and  around  the  skylight  are  blue 
curtains,  to  soften  the  light.  We  level  the  ground  with  saw-dust,  and  cover 
it  with  cocoa  matting.  It  takes  fifty-two  yards.  The  interior  is  divided  into 
four  rooms ;  three  of  them  are  8x15  feet,  and  one  8  x  10  feet.  The  reception- 
room,  ladies'  dressing-room,  the  skylight,  and  the  finishing-room,  are  the  four 
apartments. 

The  other  measurements  will  be  found  by  referring  to  the  drawing. 

35.  It  is  no  uncommon  occurrence  now  for  the  photographer  to  be  sum- 
moned to  the  homes  of  his  patrons  for  the  purpose  of  making  portraits.  There 
should  be  no  objection  to  this  when  he  is  very  generously  paid. 

fectly  as  shown  in  the  cut,  upper  section,  the  partition  between  being  removed  to  show 
the  end  of  slats.  The  figure  also  shows  end  of  rails  cut  out  back  of  roller  to  let  blinds 
down.  The  third  section  could  not  drop,  but  runs  up  an  incline  of  10  inches,  forming  a 
box  above  the  rail,  working  but  a  trifle  harder.  I  have  braces  over  the  centre  rails,  with 
a  rod  passing  through  the  sash,  making  it  very  firm ;  also,  blocks  fitted  over  the  pulleys 
ff,  to  keep  the  cord  from  running  off. — L.  M.  WHITNEY. 

35.  One  of  the  best  things  I  did  this  summer  was  to  place  screens  on  the  outside  of  my 
skylight.  Any  photographer  can  do  the  same  and  at  a  trifling  cost.  They  not  only 
keep  the  sun  off  the  glass,  and  by  so  doing  make  your  rooms  at  least  10°  cooler,  but  your 
light  is  much  softer  and  easier  to  manage.  The  idea  is  not  mine,  but  comes  from  one 
who  has  used  it  for  several  seasons,  and  who  has  recommended  it  to  many  others. 

I  obtained  ten  pieces  of  pine,  one  by  one  and  a  half  inches  wide  and  twelve  feet  long, 
and  fifteen  pieces  of  same  size,  sixteen  inches  long.  I  made  from  these  five  frames  by 
tacking  the  sixteen-inch  pieces  between  the  long  strips — that  is,  one  piece  at  each  end 
and  one  in  the  middle  to  strengthen  them.  I  used  bleached  muslin  to  cover  them,  a 
strip  four  yards  long  making  enough  to  cover  two  fans,  or  frames.  This  I  tacked  on  as 
I  would  a  background.  After  I  had  my  frames  covered,  I  fastened  a  board,  twelve 
inches  wide,  on  each  side,  running  from  top  to  bottom  of  my  skylight  (outside,  of  course). 
I  then  fastened  my  frames  at  each  end  to  the  boards  by  boring  through  the  board  and 


102  WILSON'S    QUARTEK    CENTURY    IN    PHOTOGRAPHY. 

The  annexed  cut  (Fig.  107)  is  of  a  tent,  forming  a  posing-room.     Use  a 
gray-blue  cloth  background,  about  six  feet  wide  by  seven  feet  high.      In 


FIG.  107. 


travelling,  it  is  rolled  around  the  supporting  pole;  the  top  and  the  sides, 
forming  curtains,  are  made  of  thin  stuff,  and  held  by  rings  to  the  rods  of  the 
framework,  which  are  taken  apart  with  great  ease,  to  be  packed  into  a  very 
small  compass. 

In  this  portable  atelier  excellent  portraits  may  be  obtained,  and  the  time  of 
posing  one-half  less  than  in  a  glass-house.  The  professional  photographer  and 
the  amateur  will  be  able  with  it  to  work  with  advantage  in  the  open  air,  and 
obtain  very  fine  negatives  of  portraits,  with  a  baggage  relatively  light  and  easy 
of  transportation. 

frame  and  driving  in  a  small  iron  pin.  My  frames  when  closed  down  are  about  ten 
inches  above  the  glass,  which  allows  a  nice  current  of  air  to  pass  under.  When  in  use 
they  stand  nearly  upright  or  at  any  angle  desired  to  keep  the  sun  from  shining  on  the 
glass.  I  placed  mine  so  they  lop  on  each  other  about  an  inch,  and  open  and  shut  with 
a  connecting-rod  like  our  window-blinds.  To  sum  up,  make  muslin  slats,  eighteen  inches 
wide,  the  length  of  your  skylight,  fasten  them  in  a  frame,  connect  them  together  with  a 
rod,  carry  a  line  from  each  end  of  the  rod  into  your  room,  and  work  them  at  any  angle 
you  choose. — M.  P.  BROWN. 


GLASS-HOUSE    CONSTRUCTION.  103 

36.  During  certain  seasons  of  the  year  the  light  from  the  south  shines  too 
directly  upon  the  roof  of  the  glass-room.  This  is  overcome  by  wooden  screens 
placed  upon  the  roof,  and  so  arranged  with  block  and  tackle  that  they  can  be 
raised  and  lowered  at  will.  See  the  JT.  P.  A.  plan  on  page  96. 

The  ventilation  of  the  glass-room  should  not  be  forgotten,  and  can  be  best 
secured  by  the  architect. 

And  now,  lastly,  I  add  engravings  of  the  reception-room  and  interior  of 
the  skylight  of  a  most  approved  studio,  that  of  Mr.  P.  H.  Rose,  Providence, 
R.  I.  The  splendid  study  of  the  two-  young  ladies  which  embellished  the 
Philadelphia  Photographer,  for  February,  1887,  was  made  here. 

FIG.  108. 


The  waiting-room  is  a  beauty  spot,  a  place  of  rest,  rather  than  a  place  for 
the  anticipation  of  impending  torture.  If  one  comes  to  such  for  the  purpose  of 

36.  I  employ  for  cooling  my  atelier  an  apparatus  which  is  called  a  refrigerator.  An 
India-rubber  bag,  supplied  with  valves,  is  placed  on  the  floor,  and  by  stepping  on  it  with 
the  foot  it  acts  like  a  pair  of  bellows,  and  forces  the  air  into  the  bag ;  the  air  passes 
through  an  India-rubber  tube,  and  passes  next  into  a  glass  tube ;  this  sucks  at  once  water 
from  a  vessel  and  distributes  it  through  a  point  as  a  fine  spray  through  the  room,  and  by 
evaporation  the  temperature  becomes  at  once  lower. 

I  employ  this  apparatus  not  only  for  cooling  the  atmosphere,  but  I  moisten  with  it 
also  the  interior  of  the  camera,  and  since  its  employment  I  have  not  been  troubled  with 
drying  spots. — MR.  PRUMM. 


104       WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

procuring  a  portrait  for  posterity,  with  a  sort  of  martyr-like  feeling — like  a 
lamb  led  to  the  slaughter — all  that>  feeling  will  take  its  departure  at  the 
moment  of  entering,  and  so  it  should  be. 

Here,  all  that  excellent  taste  and  artistic  judgment  could  suggest  in  the  line 
of  furniture  and  draperies  has  been  supplied,  in  order  to  secure  a  homelike 
appearance  and  to  create  a  subduing,  homelike  influence  upon  the  visitor. 

From  the  waiting-room  the  skyligKt  or  studio  is  entered.  Here,  too,  we  see 
the  evidence  of  a  master  head  and  hand,  for  all  is  well  accoutred  and  in  excel- 
lent order. 

FIG.  109. 


No  description  can  make  this  more  plain  than  does  the  autoglyph.  The 
dimensions  are  14  feet  6  inches,  by  17  feet  6  inches,  and  the  side  light  is  6  feet 
high,  by  14  feet  6  inches  wide.  The  angle  of  the  top-light  is  about  40  degrees. 
It  is  constructed  after  the  working  plans  given  (with  drawings  and  estimates) 
in  Wilson's  Photographies,  Lesson  J,  page  154. 


CHAPTEE  VIII. 


FIG.  110. 


UNDER   THE   SKYLIGHT. 

37.  AFTER  the  studio  is  constructed  and  ready  for  camera-work,  a  great  many 
needful  things  must  be  supplied  to  manage  the  light  which  enters. 

All  sorts  of  odd  "  tools "  have  been  suggested  and  are  used  by  photographers 
to  modify  the  light  as  it  falls  upon  the  sitter.  Among  these  are  screens  in 
frames,  hand-screens,  curtains,  reflectors,  and  even  "  shadow  producers." 

There  can  be  no  objection  to  this,  for  in  photography,  as  in  painting,  it  is 
perfectly  proper  that  the  artist  should  give  more  attention  to  securing  the 
desired  effect  than  he  does  to  debating  over  the  means  by  which  his  effects  are 
secured. 

37.  The  inside  curtains  used  by  Messrs.  Lcescher  &  Petsch  are  arranged  as  in  Fig.  110. 
S/S&TG  the  side  walls  of  the  atelier;  JFis  the  glass  side;  D,  the  glass  roof;  the  curtains 
on  the  glazed  side,  W,  consist  of  several  sus- 
pended pieces  of  stuff,  r,  s,  t,  which  can  be 
moved  by  sliding  them  over  the  supporting 
wire  d  d\  one  or  two  openings  may  be  made 
to  admit  the  full  light,  which  will  be  suf- 
ficient. 

Along  the  longest  direction  of  the  skylight 
wires  are  stretched  in  such  manner  that 
three  sets  of  curtains  are  placed  side  by  side, 
A  A,  B  B,  CC;  each  set  consists  again  of 
three  pieces,  o,p,q,  which  can  be  moved 
along  the  wires  at  the  pleasure  of  the  oper- 
ator; by  extending  the  curtains,  the  skylight 
may  be  covered  altogether,  or  by  drawing 
them  together,  the  skylight  may  be  made  to 
admit  all  the  light  without  obstruction ;  or 
openings  of  any  desired  size  may  be  made. 

Let  us  suppose  that  a  person  stands  at  P ; 
we  can  easily  obtain,  by  the  above-described 
arrangement,  an  illumination  like  Loescher  &  Petsch's,  by  covering  the  portion  4  of  the 
glass  side  and  the  skylight,  and  by  opening  the  portions  2  of  the  glass  side,  and  2  B  B 

(105) 


106 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  111. 


The  use  of  curtains  or  screens  overhead  and  at  the  side  light  is  an  absolute 
necessity  in  most  studios.  Suggestions  as  to  these  were  given  in  the  last 
chapter. 

38.  The  hand-screen  is  also  of  great  advantage.     By  means  of  it  effects  are 

often  obtained  which  could  not  be 
had  in  any  other  way.  Shadows  may 
be  thrown  upon  any  part  of  the  face 
during  the  whole  or  a  portion  of  the 
exposure.  By  its  careful  manipula- 
tion the  edges  of  the  shadows  may  be 
so  softened  into  the  lights  and  middle 
tints  as  to  render  the  whole  effect  har- 
monious. It  gives  a  moulding  power 
of  great  value  to  the  operator. 

Mr.  J.  H.  Kent,  Kochester,  N.  Y., 
is  its  prime  champion,  and  he  has 
taught  its  use  to  many .  (Fig.  111.) 

and  2  C  C  of  the  skylight ;  when  more  front  light  is  required,  the  part  1  A,  JB,  C  of  the 
skylight  is  opened  also.  When  we  desire  to  keep  the  light  from  the  feet  of  the  sitter,  we 
take  the  lower  corner  of  the  side  curtains  (as  at  s  t,  s  f)  and  fold  them  together,  keeping 
them  in  that  position  by  means  of  a  clamp.  Eembrandt  effects  are  produced  by  placing 
the  camera  at  For  W.  An  important  point  in  this  construction  is  that  neither  cords 
nor  rollers  are  employed,  which,  by  breaking  or  getting  loose,  cause  the  photographer 
frequently  a  great  deal  of  trouble. 

The  curtains  are  moved  by  pushing  them  with  a  rod. — DR.  H.  W.  VOGEL. 

38.  I  have  found  the  hand-screen  of  much  greater  value  than  at  first  I  supposed  it 
would  be.  At  first  I  only  used  it  to  get  effects  that  could  not  be  obtained  by  means  of 
sliding  screens  and  curtains.  Now,  however,  I  use  it  on  all  occasions,  and  can  hardly 
make  a  negative  without  it. 

Leaving  my  light  entirely  open,  I  sit  my  subject  down  almost  anywhere,  and  get  just 
the  effects  I  desire,  with  no  trouble  or  delay  in  arranging  screen  and  reflectors  and 
curtains. 

I  have  been  to  hundreds  of  dollars'  expense  in  putting  up  various  contrivances  by 
which  to  control  the  light  so  as  to  get  the  desired  softness  in  the  negative,  but  have  been 
unable  in  any  other  way  to  produce  such  results  as  are  obtained  at  once  with  the  hand- 
screen. 

I  also  find  my  sitters  invariably  do  better  than  in  the  old  way,  saying  they  never  sat 
for  pictures  so  comfortably,  and  with  so  little  fatigue  to  the  eye. 

On  the  whole,  as  simple  as  it  seems,  there  is  no  doubt  that  it  is  the  most  valuable 


UNDER    THE    SKYLIGHT. 


107 


FIG.  112. 


39.  A  hundred  methods  have  been  adopted  for.  constructing  head-screens 
and  for  using  them.  None  give  the  artist  the  power  he  has  with  the  hand- 
invention  for  the  management  of  light  that  has  been  gotten  up  since  photographs  were 
first  made. 

In  my  gallery  I  could  better  afford  to  pay  a  thousand  dollars  a  year  than  do  without 
it,  and  I  am  sure  it  would  make  more  than  that  difference  in  the  business,  to  say  nothing 
of  the  ease  and  facility  with  which  the  work  is  done. — J.  H.  KENT. 

39.  The  one  difficulty  I  find  with  the  screens  generally  in  use  is  the  amount  of 
timber  used  in  their  construction,  rendering  them  cumbersome  and  unwieldy,  and  impos- 
sible to  get  out  of  the  way  when  not  in  use.  The  object  of  this  is  to  illustrate'  my  method 
of  overcoming  this  difficulty. 

The  accompanying  cut  (Fig.  112)  tells  nearly  the  whole  story.  An  iron  rod  f  of  an 
inch  in  diameter  and  5J  feet  long  is  secured  in  a  head-rest.  One  and  one-half  feet  from 
its  upper  end  a  J-inch  hole  is  worked,  through  which  an  iron 
rod  i  inch  in  diameter  and  3  feet  long  is  tightly  driven  to  its 
centre.  This  makes  a  cross,  with  its  three  short  arms  each 
1 J  feet  in  length.  A  small  hole  is  drilled  in  the  ends  of  each 
of  these  three  arms ;  also  in  the  long  arm  1 J  feet  from  the 
point  of  crossing  of  the  two  rods.  A  light,  pine  curtain-stick 
is  secured  to  the  small  hole  in  the  long  arm  and  to  the  end  of 
one  of  the  short  arms.  A  piece  of  suitable  cloth  about  two 
yards  long  and  one  yard  wide  has  a  similar  curtain-stick  sewed 
in  each  of  its  ends.  One  end  is  then  fastened  to  the  upper 
ends  of  the  cross,  passing  over  the  stick  already  fastened  to 
the  cross  and  hanging  down  below  it,  as  shown  in  the  cut. 
Different  covers,  or  pieces  of  cloth,  may  be  prepared  to  use 
as  occasion  may  require,  as  they  can  be  changed  in  a  moment. 
When  not  in  use  the  cross  may  be  removed  from  the  head- 
rest and  hung  up  out  of  the  way,  taking  up  no  room  at  all. 
The  upper  part  may  be  readily  inclined  at  any  angle,  and  the 
whole  may  be  raised  or  lowered  as  desired.  It  has  all  of  the 
advantages  of  the  old  style,  cumbersome  wood-frame  con- 
trivance without  any  of  the  disadvantages. 

Covered  with  some  light  color,  it  is  all  that  can  be  desired  as  a  reflector ;  if  covered 
with  some  transparent  material  it  is  efficient  as  a  screen,  and  especially  so  if  the  color  be 
slightly  yellow  and  freckles  are  plentiful  in  the  subject.  If  used  thus,  due  allowance 
must  be  made  for  the  depth  and  color  of  the  shadows.  The  exposure  would  be  neces- 
sarily longer,  but  there  would  be  considerable  saving  in  the  retouching.  If,  however, 
covered  with  dead-black  or  very  dark  slate,  relieved,  when  required,  by  any  movable, 
light-colored  material,  such  as  is  generally  used  to  reflect  light,  being  hooked  on  two 
pins,  it  would  be  found  the  most  useful,  particularly  if  employed  in  the  place  of  blinds 
for  subduing  light,  producing  shadows,  shading  the  figure,  or  for  almost  any  use  to  which 
blinds  are  now  put. — JAY  DEXSMORE. 


108 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


screen,  but  several  other  forms  are  useful.      Some  are  head-screens  and  side 
reflectors  combined.     They  are  mounted  on  stands. 

The  continuous  lines  I  use  to  hold  the  screen  in  place  are  of  white,  and  some  of  red, 
to  throw  back  or  act  in  opposition  to  the  white  lines,  by  which  I  turn  it  in  any  manner 


FIG.  113. 


FIG.  114. 


conceivable.   These  red  lines  I  have  marked 
with  crossed  lines  in  Fig.  113. 

The  dotted  screens  represent  two  of  the 
many  positions  they  can  be  put  into,  either 
directly  over  the  sitter,  on  iiis  side,  in  front, 
or,  in  fact,  with  six  lines,  four  white  and 
two  red,  I  can  use  this  arrangement  any- 
where about  the  room. 

The  lines  are  better  run  through  four 
smooth  rings,  for  on  pulleys  they  are  apt  to 
get  foul  sometimes.  The  four  rings  are 
fastened  to  either  side  and  ends  of  the  lower  part  of  the  skylight  well,  and  run  down  to 
pins  or  nails  at  either  side,  or  all  running  to  one  point,  and  then  by  having  different 


UNDER    THE    SKYLIGHT. 


109 


40.  These  stands  are  often  made  available  for  other  purposes.  This  plan 
saves  floor  obstruction,  and,  as  the  changes  can  be  quickly  made,  it  will  be 
found  a  convenient  one. 

colored  cords  you  can,  after  getting  used  to  them,  work  them  very  quickly. — JOSEPH 
W.  KING. 

I  have  used  the  plan  represented  in  Fig.  114  to  my  satisfaction.  A  is  a  screen  made 
of  ordinary  white  printing-paper,  pasted  neatly  over  a  large  wire  hoop,  in  the  same 
manner  as  a  boy  makes  a  kite.  B  is  a  tin  socket  about  six  inches  long,  attached  to  one 
side  of  the  wire  hoop,  and  made  to  fit  snugly  over  the  end  of  a  jointed  bar,  (7,  which 
stands  in  an  ordinary  head-rest  column.  D  is  the  joint  in  the  bar  made  with  a  thumb- 
screw. The  above  arrangement  makes  a  universal  joint,  by  which  any  angle  can  be 
given  and  retained  in  the  screen,  which  I  use  either  as  a  modifier  or  reflector  of  light, 
as  the  case  may  require.  It  is  capable  of  doing  all  that  a  hand-screen  should  be  required 
for,  and  is  not  so  objectionable  to  the  sitter,  and  can  be  used  in  taking  pictures  of  chil- 
dren, which  I  think  would  be  difficult  with  a  hand-screen. — B.  F.  HALL. 

Mine  embraces  everything  in  the  shape  of  reflectors.  Five  years'  experience  teaches 
that  it  is  the  best  thing  yet  invented.  (Fig.  115.)  A,  head-screen;  B,  handle  to  head- 
screen  ;  C,  brace  with  two  screw-eyes  at  each  end  to  keep  head-screen  level ;  D,  cross-bar. 
At  D  there  is  a  bolt,  so  that  the  handle  B  can  be  moved  at  the  right  or  left.  The  handle 
B  runs  to  the  centre  of  the  head-screen  A,  and  is  fastened  with  another  bolt,  so  that  the 
head-screen  A  can  revolve,  thereby  making  the  light  play  on  the  face  at  one's  will.  E  E 
is  supplied  with  holes,  so  that  the  cross-bar  D  can  be  raised  and  lowered.  FFF,  side 
reflectors ;  G,  a  large  white  screen  of  unbleached  muslin,  that 
is  supplied  with  rings  at  each  side,  and  runs  on  wires.  It  can 
be  moved  on  or  off  at  will. — W.  A.  MANVILLE. 

40.  My  device  is  used  for  vignetting  in  the  camera  and  as  a 
screen  for  softening  the  side  and  top  light.  I  use  a  frame 
covered  with  tissue-paper,  fitted  in  a  frame  of  iron  wire,  so 
that  it  will  play  and  can  be  used  at  any  angle ;  it  is  fitted  in 
the  standard  of  a  head-rest.  I  have  another  frame  covered 
with  cardboard,  with  an  oval  opening,  and  painted  a  suitable 
color,  for  a  vignetter ;  they  both  fit  in  the 
wire  frame,  and  can  be  changed  in  a  moment. 
I  send  you  a  sketch  of  the  apparatus  (Fig. 
116.)  It  has  the  merit  of  cheapness,  anyway. 

-W.  H.  KlBBE. 

A  small  screen  over  or  near  the  sitter,  to 
regulate  the  light,  has  now  come  into  such 
general  use,  that  every  photographer  con- 
1  siders  it  necessary  either  to  buy  or  make  one. 
To  those  who  like  to  tinker  and  fix  up 
things  for  themselves,  I  have  a  suggestion  for  mounting  one  of  these  screens,  which  may 
be  of  service. 


FIG.  116. 


FIG.  117. 


110 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


The  combined  head-screen  and  "point  of  sight"  has  been  much  in  use.  Of 
the  former  the  standard  is  6  feet  high,  2  inches  wide,  and  j  inch  thick.  The 
feet  are  2  feet  long,  2  feet  wide,  and  f  inch  thick.  The  braces  are  1J  inches 
wide  and  f  inch  thick.  The  screen-frame  is  22  x  26  inches  outside,  f  inch 
thick,  and  the  handle  22  inches  long  by  1 J  inches  wide  by  f  inch  thick. 

Operation. — Fig.  118  shows  the  screen  as  it  is  when  not  in  use.  Fig.  119 
shows  the  screen  in  position.  It  is  hinged  at  a  to  a  little  block,  and  that  is 
fastened  with  a  shoulder-screw  to  the  standard,  which  allows  it  to  be  turned 


FIG.  118 


FIG.  119. 
.XX 


FIG.  120. 


/ 


either  way  as  you  wish  ;  and  it  being  balanced  by  the  weight  B  with  the  string 
which  goes  through  the  two  screw-eyes  C  and  D,  attached  to  the  handle  next 
to  the  screen,  allows  it  to  move  up  and  down  and  to  stop  at  any  point. 

The  stand  is  that  of  an  ordinary  head-rest,  and  on  the  rod  is  placed  the  arrangement 
shown  in  the  cut  (Fig.  117),  the  whole  being  fitted  so  as  to  turn  as  desired.  The  rod 
which  passes  through  the  ball  has  the  screen  on  one  end,  and  a  small  weight  on  the  other 
to  balance  it,  so  that  it  may  be  placed  horizontally  or  inclined,  either  way,  and  it  retains 
its  position. — J.  S.  MASON. 

The  advantage  of  the  portable  screen  and  stand  over  the  usual  blinds  or  curtains  is 
twofold — first,  the  rapidity  with  which  changes  in  the  mode  of  lighting  can  be  made ; 
and  secondly,  the  convenience  of  having  a  screen  always  at  hand  ready  for  use  in  any 
position  and  in  any  place,  suitable  to  be  employed  in  any  unforeseen  emergency.  It 
frequently  happens  that  some  considerable  adjustment  and  readjustment  of  the  blinds  are 


UNDER    THE    SKYLIGHT. 


Ill 


Point  of  Sight. — Fig.  120  is  made  of  any  light  wood,  with  a  standard  6  feet 
high,  2  inches  wide  at  the  bottom,  J  inch  at  the  top,  f  inch  thick ;  the  feet  are 
20  inches  long,  f  inch  square,  braces  light.  At  the  top  and  bottom  of  the 
standard  is  a  J  inch  hole,  and  a  string  put  through  both  holes  and  tied,  then  a 
cabinet  card  is  fastened  upon  the  string ;  being  endless,  it  moves  up  and  down 
easily  to  any  point. 

41.  Our  next  consideration  is  given  to  reflectors  or  side  screens. 

needed  before  the  artist  can  satisfy  himself  as  to  the  exact  direction  and  style  of  light 
most  suitable  to  a  subject  being  photographed;  and  as  the  larger  the  studio  the  greater 
is  the  amount  of  blinding  to  be  altered,  and  the  greater  the  amount  of  time  lost,  so  it  is 
evident  some  instantaneous  mode  of  producing  the  same  effect  with  an  equal,  if  not 
greater,  amount  of  nicety  must  be  of  considerable  help  on  occasions  when  time  presses  ; 
and,  indeed,  at  all  times,  for  the  shorter  the  period  the  sitter  is  kept  waiting  the  better 
is  it  for  his  expression  and  general  amiability. 

If  the  arrangement  be  provided  with  a  semitransparent  and  an  opaque  screen  it  would 
give  considerably  more  power  to  the  operator. 

For  occasional  use  in  unexpected  contingencies  it  is  of  considerable  service.  In  groups 
where  one  face  received  a  greater  proportion  of  light,  and  so  would  require  less  exposure 
than  the  other,  the  semitransparent  screen  would  be  found  a  useful  help.  Sometimes  a 
stray  gleam  of  sunlight  creeps  into  the  best-arranged  studio,  and  requires  a  vexatious 
amount  of  pinning  up  of  paper  and  of  general  "dodging"  before  it  is  gpt  rid  of.  Again^ 
it  may  happen  that  a  sitter  may  come  who  requires  an  unusual  amount  of  top-light,  such, 

for  instance,  as  one  whose  eye  cavity  is  but  faintly  marked, 
but  with  whom  side-light  cannot  be  entirely  dispensed  with 
— or  an  extra  gleam  of  light  from  a 
bright  cloud  low  down  on  the  horizon 
may  fall  upon  a  face  and  interfere  with 
the  first  illumination  already  devised; 
these,  and  a  multitude  of  other  occa- 
sions, will  occur  to  the  thinking  pho- 
tographer to  show  the  usefulness  of 
movable  screens. — British  Journal. 

41.   I  have  been  annoyed  a  great 
deal,  and  have  seen  others  annoyed, 
with  the  old-fashioned  side  screens.   I 
send  you  a  drawing  of  one  (Fig.  121) 
I  have  substituted,  and  find  it  admir- 
able and  a  great  power  in  my  hands. 
The  cut  explains  the  whole  thing  and 
its  use.     Being  in  a  light  frame,  it  can  readily  be  moved  about  from  place  to  place.     By 
closing  all  the  blinds  it  can  be  used  as  a  single  "solid"  screen. — H.  Noss. 
The  accompanying  cut  (Fig.  122)  shows  the  construction  of  a  very  simple  and  com- 


-pIQ 


112         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


FIG.  123. 


In  St.  Louis,  in  the  studio  of  Mr.  G.  Cramer,  I  saw  a  very  useful  con- 
trivance used  as  a  side  screen  for  modifying  the  light  on  the  subject.  It 

consisted  of  a  frame  of  the  size  and 
height  of  an  ordinary  background  frame, 
mounted  on  castors,  as  shown  in  Fig. 
123.  From  side  to  side  two  rows  of 
heavy  iron  wire  are  stretched.  On  one 
row  white  cloth  is  hung  and  on  the 
other  black  cloth,  the  one  back  of  the 
other. 

Now  it  will  be  seen  that  if  less  light 
is  wanted,  the  screen  is  so  placed  to  the 
source  of  light  as  to  •  intercept  it,  and 
the  black  screens  are  drawn,  and  vice 
versa  if  more  light  is  needed.  Or  the 
effect  may  be  modified  to  any  degree 
simply  by  arranging  the  cloth  screens 
to  suit,  or  the  cloth  may  be  pushed 

aside  altogether  or  in  part,  above  or  below,  just  as  you  please,  or  according  to 
the  object  you  Ifave  in  view. 

Very  often,  when  the  illumination  is  too  great  on  the  side  of  the  model  next 
to  the  light,  a  white  screen  is  placed  on  the  other  side,  in  order  to  reflect  the 
light  in  the  direction  desired.  A  screen  covered  with  silvered  paper  is  some- 
times used,  and  occasionally  a  mirror  for  the  same  purpose,  but  the  white 
screen  of  muslin  or  paper  is  the  best.  Blue  screens  are  sometimes  used  for  a 
like  purpose.  It  will  be  understood  that  care  should  be  taken  that  the  light- 
does  not  fall  upon  the  sitter  vertically.  This  is,  as  all  know,  prevented  by  the 
use  of  the  curtains. 

42.  It  has  been  suggested  that  the  solid,  plane  reflector  directs  the  light  too 

plete  reflector,  that  can  be  made  very  easily  and  cheaply  by  any  photographer.  The 
frame  is  three  feet  wide  and  four  feet  long.  It  is  covered  with  bleached  muslin  stretched 
tightly.  The  iron  rod  in  the  head-rest  base  is  clamped  to  the  centre-bar  of  the  frame 
with  a  bolt  and  thumb-screw,  allowing  the  frame  to  be  tilted  to  any  angle  desired,  while 
the  rod  in  the  head-rest  base  allows  it  to  be  raised  or  lowered  as  required.  A  more  con- 
venient, cheap,  or  effective  reflector  it  would  be  difficult  to  devise. — JAY  DENSMORE. 

42.  I  have  designed  a  reflector  that  is  concave,  thirty-six  inches  in  diameter,  and  made 
of  one  sheet  of  tin,  hammered  into  shape  and  afterwards  planished.  It  swings  on  pivots 
within  a  frame  just  large  enough  to  admit  of  adjusting  it  to  any  angle.  This  frame. runs 


UNDER    THE    SKYLIGHT. 


113 


violently;  that  it  is  not  under  the  quick 'control  of  the  artist,  and  should 
therefore  be  used  with  extreme  caution.  Of  course,  this  is  a  good  suggestion, 
especially  when  the  screen  material  is  white  and  the  direct  light  intense.  The 
color  should  be  governed  by  the  studio  in  which  it  is  used.  Thought  and  care 
must  be  given  to  all  of  these  things. 

To  prevent  harsh  reflections,  several  forms  of  reflectors  have  been  presented 

up  and  down  like  a  window-sash,  within  another  frame  about  six  feet  high,  which  stands 
on  legs  like  any  background-frame,  thus  enabling  one  to  throw  the  light  up  or  down  as 
the  case  may  be.  On  the  back  of  the  outer  frame  I  have  a  black  curtain  of  calico  which 
can  be  drawn  across  the  outer  frame  to  cut  off  all  reflection  except  from  the  reflector 
itself.  When  the  light  is  strong  I  hang  a  piece  of  tarletan  or  other  gauzy  material  over 
the  face  of  the  reflector  to  soften  it.  See  Fig.  124. 

PIG.  124. 


You  would  be  surprised,  upon  using  this  contrivance,  at  the  pretty  effects  that  can  be 
produced  by  it.  I  am  working  by  a  small  sky-  and  side-light,  and  I  find  it  indispensable. 
There  are  many  useful  effects  which  can  be  produced  by  it  by  using  differently  colored 
gauze  over  the  reflector.  For  instance,  for  a  round,  smooth,  light  face  and  light  hair, 
a  buff  color  gives  pretty  shades,  greater  strength  or  contrast  in  the  negative.  For  sharp 
features,  sallow  or  tanned,  a  blue  color  is  useful.  The  inner  frame  £an  be  fastened  at 
any  point  desired. — M.  M.  GBISWOLD. 

In  making  "Kembrandt"  pictures  the  usual  routine  of  operations  is  abandoned  and 
reversed.  Instead  of  at  the  side  of  the  subject  nearest  the  camera,  the  main  light  comes 
from  behind  the  sitter,  as  it  were,  or  falls  upon  the  side  of  the  subject  from  the  camera, 
the  side  toward  the  camera  being  in  shadow.  To  get  detail  in  this  shadowed  side  it  is 

8 


114 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


— "  concave,"  "  compound,"  "  eccentric,"  and  what  not,  selections  from  which 
are  described  in  the  notes  below. 

necessary  to  reflect  some  light  upon  it,  and  to  avoid  a  multiplicity  of  screens  and  reflec- 
tors.   For  this  I  have  contrived  the  apparatus  described  below.    (Fig.  125.) 

A  B  CD  represent  a  light  frame  of  wood,  about 
six  feet  high  and  three  and  a  half  feet  wide. 
EFEF  are  two  doors  or  wings  turning  on 
pivots  at  the  points  A  and  B,  and  also  on  two 
other  pivots  at  G  G  G  G,  consequently  giving  a 
universal  movement.  X X XX  are  four  inner 
wings  moving  on  hinges  on  the  frame,  whereby 
you  may  enlarge  or  decrease  the  size  of  the 
opening,  the  lower  wing  moving  on  two  pivots 
at  PP.  All  this  is  lined  on  the  back  with 
strong  paper  and  black  muslin,  and  on  the  front 
with  pure  white  paper. 

The  application  of  the  counter-reflector  may 
be   better    understood    by    the   accompanying 
drawings. 
Let  A  B,  Fig.  126,  1,  represent  a  block  of  wood,  and  the  light  shining  on  it  in  the 

direction  of  the  arrow — any  attempt  to  photograph  this  in  its  present  state  of.illumi  nation 

would  be  impossible.     The  dark  shadow  at  B 

would  be  devoid  of  all  details,  and  the  high 

light  at  A  would  be  too  intense.     Upon  bring- 
ing up  the  reflector  at  (7,  the  effect  is  to  drive, 

as  it  were,  the  shadow  back  again  toward  A, 

producing  an  unnatural  lighting,  as  shown  in 

Fig.  126,  2,  causing  a  squinty  appearance  in 

the  sitter,  caused  by  being  raked  between  two 

fires.    Now  the  counter-reflector  has  the  effect 

of  doing  away  with  this  completely  (Fig.  126, 

3).     It  throws  the  light  in  the  direction  of  the 

lines,  and  we  have  the  natural  effect  of  Fig. 

126,  1,  only  greatly  subdued,  with   perfectly 

transparent  shadows,  offering  no  strong   nor 

harsh  contrasts  against  the  high  light;  A,  as  it 

were,  counter-reflecting  the  reflection  of  B,  thus  preventing  that  shadow  which  otherwise 

would  have.hung  over  the  centre. 
This  arrangement  also  serves  a  good  purpose  when  making  pictures  in  the  usual  way, 

and  is  specially  useful  where  there  is  no  side-light,  in  scattering  the  shadows  that  are 

apt  to  occur  in  such  cases  under  the  eyes,  nose,  and  chin,  and  in  relieving  the  frowns  of 

unwilling  sitters.     It  is  patented  by  Mr.  Henry  Kurtz. 


FIG.  126. 


UNDER    THE    SKYLIGHT.  115 

43.  Sometimes  when  a  skylight  is  found  uncontrollable,  use  has  been  made 
of  a  sub-studio,  so  to  speak,  constructed  inside  the  larger  one.  Such  a  plan 
was  suggested  some  time  ago  by  Mr.  E.  J.  Foss,  Boston.  It  was  contrived  as 
described,  and  is  illustrated  below.  (Fig.  127.) 

FIG.  127. 


It  is  called  a  "  shadow  chamber/'  and  is  a  conglomeration  of  sliding  curtains 
which  can  be  moved  quickly,  securing  an  endless  number  of  eifects. 

Mr.  Foss's  studio  has  a  side  light,  thirteen  feet  wide  and  ten  high,  connecting 
with  the  skylight,  which  is  thirteen  feet  square ;  the  glass  is  all  ground ;  the 
angle  of  the  skylight  is  thirty-five  degrees ;  there  is  a  space  from  the  side  and 
skylights  to  the  back  wall  of  nine  feet ;  in  the  ceiling  of  this  space  is  a  window 

43.  My  illuminating  apparatus  is  only  intended  for  busts  and  the  general  figure, 
although  children  can  easily  be  taken  full  length.  Neither  is  it  intended  for  use  in  a 
very  small  operating-room,  for  it  would  only  be  in  the  way,  and  the  light  in  such  small 
rooms  can  be  easily  regulated  by  top  and  side  screens  and  blinds.  In  using  the  platform 
I  generally  let  in  all  the  light  I  can  get  from  the  sky  and  side  lights  (but  not  sunlight), 
and  then  regulate  the  screens,  blinds,  and  reflectors  attached  to  the  uprights  on  the 
platform.  By  moving  it  to  different  positions  under  the  skylight,  in  conjunction  with 
screen,  etc.,  I  can  get  any  light  I  want  with  very  little  trouble. 

The  platform,  or  floor,  is  made  of  six-inch  fencing-boards,  one  inch  thick,  planed  off 
on  one  side,  and  two  layers  are  running  crosswise,  and  nailed  firmly  together.  It  is  five 
feet  square,  with  the  four  corners  cut  off  and  set  on  common  bedstead  castors  three 
inches  from  the  edge  on  each  side.  Near  the  corner  are  bored  four  two-inch  holes  three 
feet  apart,  into  which  are  put  four  uprights  two  inches  square,  with  stanchions  at  the 
bottom;  the  uprights  are  seven  feet  high,  and  are  framed  together  at  top  by  pieces 


116 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


some  three  feet  wide,  which  extends  clear  across  the  room ;  this  light  is  used 
for  the  purpose  of  lighting  up  the  backgrounds,  of  which  there  are  several  on 
rollers,  fastened  to  the  ceiling ;  the  three-feet  light  does  not  reach  the  sitters, 
they  being  in  the  shadow  chamber.  It  is  said  to  work  very  satisfactorily. 

seven-eighths  by  one  and  a  half  inches,  to  hold  all  steady ;  they  are  also  braced  at  top 
and  bottom,  as  shown  in  Fig.  128. 

Between  the  uprights  on  each  side  are  two  movable  frames  two  feet  ten  inches  by  two 
feet  three  inches  long ;  the  four  screens  or  reflectors  are  inserted  between  the  uprights, 
and  a  two-inch  wood-screw  passes  loosely  through  them  six  inches  from  the  bottom,  and 
screwed  firmly  into  the  upright  post.  Fifteen  inches  from  the  platform  is  the  bottom 
frame,  marked  X,  and  four  feet  from  the  floor  are  the  two  top  frames  marked  0.  In 
front,  hung  on  the  face  of  the  first  are  two  long  frames  eighteen  inches  by  six  feet  long, 
hung  on  common  door-hinges. 

The  background  is  five  by  seven  feet,  painted  as  described  in  Mosaics  for  1877,  page 
48 ;  on  top  is  a  frame,  marked  5,  two  feet  ten  inches  by  four  feet  six  inches,  and  turned 


Fro.  128 


FIG.  129. 


FIG.  130. 


on  two  screws  at  the  back,  the  same  as  side  screens.  It  acts  as  a  head-screen.  This 
screen  is  raised  or  lowered  to  suit  with  a  notched  stick ;  all  the  top  frames  are  covered 
with  thin,  bleached,  yard-wide  muslin. 

The  two  bottom  side  reflectors,  which  are  opaque,  and  painted  a  light  blue,  act  as 
reflectors  to  light  up  the  shadows  under  the  eyes,  nose,  chin,  etc.  On  the  two,  side  top 
and  long  front  screen,  marked  2  and  0,  are  four  green  opaque  curtains,  that  roll  up  the 
same  as  a  common  window-shade,  and  can  be  pulled  down  to  the  floor,  shutting  off  all 
light  from  the  sides.  On  the  back  corners  of  the  four  reflectors,  marked  0  and  X,  is 
fastened  a  small  band  that  passes  over  a  small  pulley  fastened  in  the  upright  post,  and 
at  the  other  end  is  a  small  weight  to  counterbalance  the  weight  of  the  frame  when 
thrown  back,  which  makes  it  stay  in  position.  In  front  is  also  a  thin  white  curtain, 
marked  6,  which  can  be  pulled  down  three  feet,  or  rolled  entirely  up.  The  background 


UNDER    THE    SKYLIGHT.  117 

The  real  fact  is  that  the  slightest  interference  with  the  light  as  it  comes  from 
the  glass  above  or  at  the  side  will  change  the  effect  upon  the  sitter  and  in  the 
negative. 

44.  And  now,  since  photographing  colors  is  understood,  we  may  also  use 
them  reflected  carefully  upon  the  model.  The  artist-photographer  uses,  or 
endeavors  to  use,  light  just  as  he  would  use  paiut  on  his  brush.  Light  is  his 
paint ;  and  in  the  proper  distribution  of  it  over  his  subject  largely  consists  the 
true  art  of  the  photographer.  But  the  acquirement  of  this  art,  like  everything 

sets  back  one  foot  from  the  back  part,  and  is  fastened  to  a  two-inch  post  behind,  which 
fits  in  a  two-inch  hole  bored  in  the  platform,  and  turns  on  a  pivot,  so  that  the  background 
can  be  turned  freely  around  to  or  from  the  light,  and  thereby  graduate  it  more  or  less, 
and  leaves  room  to  go  in  to  arrange  the  head-rest,  etc.,  which  is  no  small  item.  All  the 
frames  are  made  of  stuff  seven-eighths  by  one  and  a  quarter  inch  wide ;  the  whole  is  very 
light,  and  can  be  shoved  or  pulled  about  at  pleasure. 

Here  we  have  a  set  of  frames  so  arranged  that  they  are  reflectors,  counter-reflectors, 
transparencies,  or  non-reflectors,  at  will,  and  all  under  your  thumb.  Here  you  have  the 
control  of  direct,  diffused,  and  reflected  light,  and  you  ought  to  be  able  to  control  with  it 
any  kind  of  front,  top,  side,  or  back  light.— G.  W.  CODDINGTON. 

I  wish  to  call  attention  to  a  prevailing  source  of  error  in  the  lighting  of  white  drapery, 
a  careful  consideration  of  which  would  necessitate  a  change  in  the  modus  operandi  of 
some  of  our  operators  in  handling  this  class  of  subjects. 

Take  a  lady  sitter,  with  little  or  no  color  in  the  face.  Pose  her  some  distance  from 
the  lights ;  draw  your  curtains ;  trundle  up  your  head-screen,  and — study  that  face  care- 
fully. What  have  you  got?  Marble !  And  marble  you  will  get  in  your  negative.  This 
illumination  might  answer  for  a  swarthy  face ;  certainly  not  for  a  fair  one.  And  if  this 
be  true  of  the  face,  how  much  more  so  in  the  case  of  white  drapery,  which  must  have 
light,  and  plenty  of  it,  or  you  get  no  shadows?  A  few  experiments  with  a  white  statue 
will  show  you  that  a  strong  light,  properly  controlled,  will  give  you  better  detail  than  a 
weak  one.  Head  and  side  screens  may  be  good  servants ;  they  are  certainly  bad  masters. 
A  soft  light  is  not  indispensable  in  the  production  of  a  soft  negative.  Brilliancy  and 
hardness  are  by  no  means  synoymous  terms. 

There  is  another  thought  in  this  connection  which  may  be  worth  considering.  You 
sometimes  notice  a  face  on  the  street  which  fairly  sparkles  with  animation ;  but  when 
you  come  to  photograph  that  face,  it  seems  dull  and  insipid.  Is  the  sitter  altogether  to 
blame  for  this  ?  May  not  the  subdued  light  of  the  studio  be  somewhat  responsible  for 
this  lack  of  expression  ?  The  scale  in  the  gamut  of  expression  contains  an  indefinite 
number  of  octaves.  A  weak  light  may  fail  to  detect  the  beauties  that  a  strong  one 
reveals. — GEORGE  SPERRY. 

44.  For  heads  and  half-length  portraits  it  is  quite  unnecessary  to  use  the  side-light  so 
largely  as  is  usual ;  the  top-light,  when  under  judicious  control,  will  give  the  better  and 
more  artistic  effects  of  light  and  shade.  In  order  to  be  really  useful,  a  side-light  must 
be  taken  on  a  level  with  or  above  the  horizon ;  the  best  light  is  one  that  falls  on  the  sitter 


118        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

else,  demands  much  study  and  long  experience,  as  well  as  adaptation  to  times, 
seasons,  colors,  complexions,  etc. 

M.  Klary,  a  veteran  Parisian  photographer,  professes,  by  the  aid  of  a 
" screen  with  a  movable  colored  head  to  it,"  to  have  put  into  the  hands  of 
photographers  just  the  "  brush"  which  they  require  wherewith  to  "  paint  with 
light."  I  shall  not  attempt  any  minute  description  of  the  apparatus.  It  is 
described  to  me  as  extremely  simple,  consisting  of  a  screen  of  white,  blue,  pale 
red,  or  pale  orange  calico,  according  to  circumstances,  fixed  on  a  stand  with 
an  ingeniously  contrived  motive  power.  This,  placed  behind  the  subject, 
enables  the  operator  to  regulate  and  distribute  the  lights  absolutely  at  will, 

at  an  angle  of  45  degrees.  It  is  necessary  that  the  light  be  balanced  in  accurate  propor- 
tion, the  time  of  exposure  sufficient  to  set  forth  the  lighting,  and  the  development  adjusted 
according  to  the  exposure.  The  lighting  of  the  face  should  be  balanced  in  such  a  way 
that  the  contrasts  may  not  be  simply  black  and  white,  but  a  soft  gradation  of  all  the 
intermediate  tones,  as  well  in  the  lights  as  in  the  shadows,  so  as  to  produce  a  graceful 
and  artistic  picture.  The  greatest  distance  from  the  eye  of  the  beholder  should  be  darkest 
in  tone,  the  nearest  portion  the  lightest,  and  every  graduation  between. 

Of  the  three  lights  used  in  the  studio,  the  diffused  may  be  employed  in  the  greater 
quantity,  the  reflected  must  be  more  restrained,  and  the  direct  used  more  sparingly  and 
judiciously.  The  position  of  the  sitter  should  be  under  the  principal  and  strongest  light. 
It  is  best  to  employ  a  soft  and  slightly  diffused  light,  combining  in  due  proportions  the 
top  and  side.  This  is  readily  obtained  by  use  of  the  head-screen  (which,  being  con- 
structed with  various  movements,  will  enable  the  operator  to  have  this  light  under  perfect 
control).  It  should  be  placed  by  the  side  of  the  sitter,  nearest  to  the  light,  and,  of 
course,  outside  the  focus  of  the  desired  picture.  It  must  be  elevated  above  the  head, 
raised  or  lowered  and  turned  to  the  required  angle  until  the  operator  observes  the  true 
and  best  effect  upon  the  shades  and  lines  of  the  face.  There  will  now  be  seen  a  general 
and  diffused  light  over  the  whole  of  the  figure,  but  a  little  predominant  on  the  side  nearest 
the  light ;  then  open  a  small  accidental  side-light  quite  in  front  of  the  sitter,  which  will 
fall  upon  the  prominent  parts  of  the  face ;  if  the  eyes  are  sunk  deeply,  lower  the  screen 
a  little,  and  move  it  slightly  toward  the  shaded  side  of  the  face ;  it  will  thus  increase  the 
top-light,  and  bring  the  face  into  bold  -  relief;  the  shaded  side,  though  slightly  darker 
than  the  other,  will  remain  soft  and  full  of  detail. 

Observe  that  the  reflex  of  the  eyes  must  be  the  same  in  each ;  these  luminous  points 
have  their  place  on  the  upper  part  of  the  eye  and  nearest  the  side-light — not  in  the 
middle.  If  the  reflex  appears  in  one  eye  only,  the  face  is  too  far  away  from  the  side- 
light; then  move  your  camera  and  turn  the  face  toward  the  side-light  until  these  lumi- 
nous points  appear  on  both  eyes ;  the  head  will  then  be  well  lighted,  and  the  classic 
outline  of  the  nose  well  rendered.  A  beautiful  and  often  unforeseen  lighting  will  be 
discovered  by  the  movements  of  this  screen.  Being  made  of  translucent  materials,  it 
softens,  filters,  and  slightly  diffuses  the  light  over  the  head  of  the  sitter,  and  is  an  im- 
mense power  in  the  hands  of  a  skilful  operator  for  obtaining  in  any  studio  those  fine 


UNDER    THE    SKYLIGHT.  119 

until  all  is  brought  into  due  harmony  and  good  keeping  in  the  "  picture"  which 
he  is  about  to  reproduce.  The  above  instrument,  combined  with  the  use  of  a 
concave  reflector  of  a  pale  rose  or  yellow  tint,  enables  the  operator  to  bring  out, 
in  relief,  all  the  features  of  a  portrait  which  require  to  have  more  light  thrown 
upon  them.  The  productions  of  M.  Klary,  obtained  by  the  above  process,  are 
very  pleasing,  and  have  been  much  admired  in  Paris.  Another  part  of  his 
system  also  is  that  the  whole  face,  in  a  photographic  portrait,  should  be  more 
or  less  shaded,  none  of  it  left  absolutely  crude  or  white ;  just  as  in  playing 
the  violin,  to  borrow  an  illustration  from  the  sister  art,  no  string  is  ever  left 

effects  of  light  and  shade  which  produce  a  perfect  picture  and  which  could  not  be  easily 
produced  by  any  existing  arrangement  of  blinds  or  curtains.  With  taste  and  a  little 
practice  its  use  will  become  intuitive. 

It  is  necessary  to  soften  the  edges  of  the  shadows,  in  case  of  need,  with  a  pure  and 
delicate  reflected  light ;  this  is  done  very  readily  by  means  of  the  concave  reflector,  used 
in  accordance  with  the  judgment  of  the  operator.  It  should  be  turned  towards  the  sitter 
in  such  a  manner  as  to  throw  a  concentrated  light  upon  that  part  of  the  face  under  and 
behind  the  eye,  as  well  as  the  darker  portions  of  the  neck,  and  you  will  thus  avoid  the 
spot  of  reflected  light  appearing  in  the  eye.  A  perfectly  exact  position  of  the  reflector 
is  as  essential  as  for  the  head-screen,  in  order  that  the  proper  balance  of  lighting  may  be 
obtained. 

For  lighting  a  la  Rembrandt  do  not  change  the  position  of  the  face,  but  move  your 
camera  so  as  to  obtain  a  view  of  the  other  cheek,  and  with  some  slight  modifications  of 
the  head-screen,  this  lighting  will  be  as  perfectly  rendered  as  the  other ;  it  is  not  here 
necessary  to  use  the  reflector,  the  head-screen  alone  will  regulate  the  top-light,  which 
must  be  used  sparingly,  so  that  it  may  not  fall  upon  the  points  where  the  middle  tones 
are  wanted. — C.  KLARY. 

As  regards  the  best  position  of  the  camera,  it  has  already  been  stated  that  no  lens  has 
a  perfectly  flat  field ;  hence,  for  a  standing  figure  requiring  a  flat  field,  it  is  of  the  utmost 
importance  that  the*  camera  should  be  so  positioned  as  to  favor  the  lens.  This,  for  card 
portraits  (equivalent  focus  of  lens  about  nine  inches,  back  focus  six  inches,  and  distance 
of  subject  eighteen  feet,  the  camera  without  a  swing-back),  is  as  follows  :  Height  of  centre 
of  lens  from  the  floor,  about  four  feet  ten  inches ;  rising  front  of  camera  to  be  elevated 
one-quarter  inch;  and  then  the  image  made  to  occupy  the  centre  of  the  plate,  i.  e.,  equi- 
distant between  the  top  and  bottom  of  the  screen.  To  effect  this  the  camera  will  require 
to  be  tilted  forward  slightly,  which  insures  a  more  natural  view  of  the  face  than  when 
placing  the  camera  lower  and  level,  in  which  case  the  view  of  the  face  obtained  is,  as  it 
were,  that  of  looking  up  into  it.  Having  got  the  image  in  the  centre  of  the  plate,  focus 
for  the  eye,  and  then  for  the  chest,  or  some  prominent  object  on  the  chest,  as  a  watch 
chain.  Now  halve  the  focus  between  this  and  the  eye,  when  it  will  be  found  that  the 
resulting  picture  will  be  evenly  defined  throughout  its  entire  length. 

A  sitting  figure  requires  the  camera  to  be  placed  at  a  proportionally  lower  elevation, 
and  here  a  swing-back  is  of  great  advantage.  Indeed,  portraits  beyond  the  half-plate 


120 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY 


entirely  "open,"  nor  any  true  note  produced  without  the  feeling  and  action  of 
the  finger  of  the  musician.  In  a  word,  the  system  of  M.  Klary  was  intended 
to  replace  advantageously  the  whole  clumsy  apparatus  of  curtains,  blinds,  shut- 
ters, reflectors,  counter-reflectors,  headscreens,  etc.,  but  it  has  not  yet  found 
general  adoption. 

45.  Almost  as  countless  as  the  stars  is  the  variety  of  backgrounds  in  use. 

size  should  never  be  attempted  without  this  adjunct  to  the  camera;  for,  as  has  been 
shown  already,  larger  or  longer  focus  lenses  are  much  more  sensitive  to  differences  of 
distance ;  and  in  a  sitting  figure  the  feet  are  often  .as  much  as  twenty-four  inches  or 
more  in  advance  of  the  face.  This  occasions  nearly  a  quarter  of  an  inch  of  difference  of 
focus  for  a  twenty-inch  focus  lens,  and,  therefore,  without  a  swing-back,  allowing  the 
top  of  the  screen  or  slide  to  be  pushed  out  that  distance,  definition  of  the  legs  and  feet 
simultaneously  with  the  head  cannot  be  secured. 

Photographers  accustomed  to  work  with  short-focussed  lenses,  i.  e.,  at  short  distances 
from  the  subject,  often  complain  of  lack  of  brilliancy  and  roundness  in  their  pictures 
when  taking  to  the  use  of  longer-focus  lenses,  or  working  at  greater  distances  from  the 
subject.  Now,  in  most  cases,  this  is  simply  a  question  not  of  lens,  but  of  lighting,  for  it 
is  obvious  that  the  direction  and  amount  of  light  suitable  for  a  subject  at  twelve  feet 
distance  requires  considerable  modification  for  one  at  twenty  feet — JOHN  L.  GIHON.. 

45.  I  use  a  circular  background.  As  will  be  seen  by  Fig.  131,  it  consists  of  a  muslin  disk, 
mounted  on  framework,  which  revolves  on  an  axis  affixed  to  an  ordinary  head-rest.  The 

diameter  is  4J  feet.  Unbleached  muslin  is  used, 
painted  with  a  neutral  tint  and  gradated.  It  is 
started  on  a  revolution  at  the  moment  of  ex- 
posure.—C.  W.  MOTES. 

It  is  not  my  intention  to  rob  Mr.  Motes  of 
any  laurels  that  may  be  due  him,  but  simply 
to  mention  that  I  have  made  a  similar  back- 
ground. My  modification  is -as  follows:  Instead 
of  being  a  "revolving  background,"  it  only 
works  half-way  round,  or  less,  as  the  case  may 
be,  by  a  pendulum.  It  is  made  with  four  arms, 
about  four  inches  apart.  It  is  graduated  with  a 
light  color  (or  a  darker  one  than  the  background) 
from  the  bottom  to  the  color  of  the  background 
at  the  top.  Then,  by  setting  it  in  motion,  you 
get  a  graduated  shadow  on  one  side  of  the  head, 
and  thereby  save  time  and  trouble  in  "  wool- 
ing"  the  negative  during  printing. — W.  R. 

HOLYOAKE. 

I  was  showing  M.  Salomon  some  examples  of  the  work  of  Mr.  Kurtz,  and  describing 
to  him  the  cone  background  and  its  value  in  securing  light  and  shade  to  relieve  the 


FIG.  131. 


UNDER    THE    SKYLIGHT. 


121 


FIG.  132. 


Almost  as  hard  as  the  stars  to  comprehend  are  the  reasons  why  photographers 
use  -such  backgrounds  as  they  sometimes  do. 

One  general  fault  is  the  use  of  backgrounds  of  too  large  dimensions.  Not 
only  this,  the  desire  seems  to  prevail  for  "  wide-angled  "  backgrounds — i.  e.,  such 
as  include  trees  and  plants  of  the  various  climes  of  the  world ;  architecture  of 
various  periods ;  lakes,  rivers,  mountains,  parks,  villas,  and  "  all  out  doors " 

figure.  He  informed  me  that  he  had  been  using  an  arrangement  with  a  similar  end,  but 
somewhat  different  in  construction,  and  having  also  a  somewhat  more  comprehensive 
aim.  His  background  forms  a  curve,  or  the  arc  of  a  large  circle,  the  chord  of  which  arc 
would  be  about  nine  feet.  Attached  to  this  is  a  ridge-shape  canopy  of  semitransparent 
material.  This  canopy  opens  at  the  ridge,  and  is  hinged  to  the  background  at  each  side, 
so  that  it  can  be  opened  to  admit  a  portion  of  direct  light.  As,  however,  it  is  chiefly  by 
a  high  side-light  that  M.  Salomon  illuminates  his  figures,  the  curved  background  plays 
the  most  important  part  in  his  lighting.  At  the  back  is  a  rod,  e  (Fig.  132),  terminating 
in  a  series  of  loops  or  pulleys.  Through  these  pass 
cords  which  are  attached  to  the  canopies  c  and  d.  The 
cords  are  all  brought  to  a  position  behind  or  at  the 
side  of  the  background,  where  the  operator  can  readily 
manipulate  them,  each  cord  having  a  counterpoise  at- 
tached, so  as  to  maintain  the  canopy  in  any  position 
into  which  it  is  pulled  by  the  manipulator.  The 
wings  and  canopy  b  and  c  are  light  frames  covered 
with  thin,  transparent  white  muslin,  transmitting  some 
light,  but  arresting  or  breaking  up  direct  rays  of  sun- 
light. At  each  end  of  the  canopy  c  is  attached  a  piece 
of  thin  muslin,  which  we  have  not  figured,  as  it  would 
have  somewhat  confused  the  diagram.  It  is  the  same 
width  as  the  wings,  over  the  top  of  each  of  which  a 
piece  hangs,  to  maintain  the  continuity  between  the 
wing-screens  and  the  projecting  canopy.  The  canopies 
d  are  also  light  frames  covered  with  thick  white  calico, 
transmitting  very  little  light.  The  background  rests 
on  three  feet,  one  at  each  side  and  one  in  the  middle ; 

these  each  project  behind  about  eight  inches,  to  give  firmness  and  steadiness ;  each  foot 
has  a  large  castor,  to  permit  the  whole  to  be  wheeled  round  easily  into  any  position. 
The  wings  are  hinged  so  as  to  hang  an  inch  or  two  from  the  ground,  and  are  very  easily 
moved  backward  and  forward.  The  background  is  papered — in  that  used  by  M.  Adam 
Salomon,  with  salmon-colored  printing-paper.  The  sitter  is  placed  within  the  curve, 
and  the  background,  which  is  made  to  run  easily,  is  moved  round  him  until  the  right 
effect  is  produced,  the  curved  screen  being  used  to  regulate  the  amount  of  light  admitted 
on  the  lighted  side,  and  to  act  as  a  reflector  on  the  shadowed  side,  as  well  as  to  form  a 
background,  which  by  its  light  and  shade  gives  space  and  relief  to  the  figure. — G. 
WHARTON  SIMPSON. 


122 


WILSON'S    QUAKTER    CENTURY    IN    PHOTOGRAPHY 


crowded  upon  one  10  x  12  sheet.  If  a  full  figure  of  a  bride  is  taken,  the  chance 
is  good  for  including  all  this  in  the  picture.  Then  it  might  harmonize  with 
her  "  bridal  tour."  But  if  a  seated  subject  is  offered,  what  must  become  of  the 
background  if  the  lens  is  brought  up  to  any  proper  approach  ?  Try  having 
pretty  "bits"  painted  for  your  backgrounds  on  sheets  5  x  6  or  thereabouts,  and 
you  will  like  them  better. 

Revolving,  oscillating,  curved,  circular,  and  swinging  backgrounds  are  among 
the  novelties. 

The  Kurtz  cone  background  did  not  seem  to  secure  many  adherents,  though  deserving 
a  better  fate.  Fig.  133  represents  it  entire.  It  is  made  of  papier-mache,  six  feet  in 
diameter  by  three  feet  deep,  mounted  on  a  rod  which  fits  any  ordinary  head-rest  stand ; 
the  latter  is  fastened  to  a  wooden  platform  on  castors,  and  is  furnished  with  a  handle,  A. 
As  the  whole  affair  weighs  but  a  few  pounds,  it  can  readily  be  moved  and  adjusted  to 
any  part  of  the  room  or  light.  The  interior  is  painted  or  sanded  to  any  degree  of  shade 
desirable.  It  will  be  readily  understood  that  any  light  coming  from  one  side,  must 
illumine  that  part  of  the  interior  furthest  from  it,  and  per  contra  leave  the  nearest  side 
in  comparative  shade.  By  turning  it  full  to  the  light,  there  is  no  shade,  and  you  get  a 
very  light  background ;  then  upon  turning  it  from  the  light,  you  get  it  almost  black,  if  you 
wish  it  so.  An  example  of  its  peculiar  and  extraordinary  effect  will  perhaps  be  better 
understood  by  contemplating  Fig.  134. 


FIG.  133. 


Fro.  134. 


Let  A  B  represent  the  side-light,  D  Eihe  background,  Fihe  sitter's  head,  and  H  the 
camera.  Now  you  plainly  notice  that  the  rays  of  light  from  the  window  A  B  illumine 
only  about  that  portion  of  the  background  at  the  left  of  the  line  D,  whilst  the  portion  at 
the  right  of  D  is  left  in  its  own  shadow.  Now  as  the  light  falls  on  the  sitter  F,  the  side 
turned  towards  the  light  only  is  illuminated.  The  sitter,  as  viewed  from  the  camera  in 


UNDER    THE    SKYLIGHT.  123 

46.  All  careful  observers,  and  all  good  photographers,  know  what  a  flat, 
repulsive  effect  is  given  to  a  face  when  the  light  is  evenly  diffused  all  over  it. 
There  is  no  contrast,  no  gradation  of  half  tones,  and  the  effect  is  spiritless. 

It  is. just  so  with  a  background  of  one  unbroken  tint;  and  our  eminent 
artists  have  resorted  to  several  means  by  which  they  can  easily  secure  a  grada- 
tion of  tint  upon  the  background. 

To  get  a  little  shadow  on  the  top  of  the  background,  a  stationary  screen  is 

the  direction  of  If,  has  the  high-light  _F  admirably  relieved  by  the  darker  portion,  whilst 
the  shadow  part  of  the  sitter  is  as  well  relieved  by  the  lighter  portion  of  the  background. 
No  matter  from  what  direction  your  subject  is  lighted,  the  background  immediately 
assumes  the  opposite  lights  and  shades,  and  an  extraordinary  relief  is  at  once  obtained. 
By  a  little  judgment  and  management  it  can  be  made  exactly  suitable  for  all  complexions. 
In  the  case  of  a  group  of  two,  the  darker  person  should  be  placed  against  the  lighter 
portion  of  the  background. 

A  background  for  all  gradations  of  tints  was  invented  by  my  good  Italian  friend,  Cav. 
Ottavio  Baratti.  A  few  words  and  the  accompanying  figure  illustrate  it  in  a  sufficiently 
clear  manner.  Take  a  strip  of  muslin  of  suitable  width,  six  -pIQ 

metres  long,  and  colored  progressively  and  with  continuous 
gradation  in  such  a  manner  that  at  the  opposite  ends  there 
shall  be  one  metre  of  white  and  one  metre  of  black.  These  two 
ends  are  joined  together  and  thus  form  an  endless  band.  This 
is  placed  on  a  wooden  roller  supported  by  a  framework  and  put 
in  motion  by  two  wheels;  at  the  bottom  another  free  roller 
keeps  the  cloth  stretched. 

The  motion  may  be  communicated  by  hand  by  means  of  a 
crank,  or  by  clockwork. 

If  the  operator  wants  a  dark  ground,  he  brings  the  black  part 
to  the  front,  and  keeps  it  there ;  should  he  wish  it  rather  lighter,  he  begins  at  the  white 
and  passes  gradually  to  the  darker  tints. 

Another  advantage  of  this  apparatus  is  to  keep  the  backgrounds  of  the  pictures  free 
from  spots  or  stains,  as  the  cloth  being  in  motion  during  the  pose,  it  can  leave  no  traces 
of  them. 

The  construction  is  simple,  presents  no  difficulty,  and  also  costs  but  little. 

46.  The  numerous  ways  in  which  a  background  or  accessory  may  be  used  are  not 
apparent  at  first  sight.  Frequent  use,  continued  experiment,  and  study  alone  reveal 
them.  Much  pleasure  is  afforded  me  when  I  see  that  my  works  have  been  used  under- 
staiidingly ;  and  pleasure,  mingled  with  surprise,  when  they  are  put  to  new  and  good 
use  upon  which  I  had  not  calculated.  My  respect  for  a  photographer  increases  with  his 
advancement,  and  I  feel  more  firmly  bound  to  do  for  him  my  best  when  executing  his 
commands. 

We  "are  all  stimulated  to  our  highest  activity  when  much  is  demanded,  and  we  are 
interested  when  working  out  an  idea  above  the  level  of  our  everyday  pursuits  or  thoughts. 


12-i        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

suspended  horizontally ;  it  is  partly  over  the  head  of  the  sitter,  and  raised  and 
lowered  by  means  of  cords  and  pulleys.  Another  shadow  is  thrown  in  behind 
the  sitter  by  moving  a  very  dark  triangular  screen,  about  one-half  the  size  of 
the  background  (which,  by  the  way,  must  be  white,  or  very  light),  up  and  down 
during  exposure  between  it  and  the  sitter. 

This  will  account  for  the  time  which  some  of  our  enthusiastic  friends  spend  when  the 
presence  of  a  good  model  or  sitter  offers  the  opportunity. 

The  professional  artist-painter  of  landscapes  or  figures  is  not  content  with  the  practice 
found  in  the  execution  of  his  usual  subjects,  but  periodically  takes  days  and  weeks  for 
the  close  study  of  nature,  in  order  that  he  may  advance  to  a  higher  plane. 

Eecently  I  have  seen  great  improvements  in  the  work  of  an  artist  friend  after  only  an 
eight  days'  sketching  trip  on  the  Hudson ;  and  I  have  no  doubt  but  that  photographers 
will  find  themselves  benefited  if  they  will  frequently  practise  posing,  composition,  and 
landscape  photography  solely  as  studies.  The  real  falls  short  of  the  ideal,  and  the  pho- 
tographer should  in  his  ideas  be  in  advance  of  his  power  of  execution.  When  he  is 
satisfied  with  his  results,  then  he  may  be  certain  he  has  struck  his  highest  level,  and  is 
in  danger  of  receding  or  being  eclipsed  by  a  more  ambitious  and  persistent  worker.  I 
would  urge  study,  because  the  mechanical  photographers  are  being  gradually  dropped 
from  our  ranks,  and  ere  long  it  will  be  generally  conceded  that  the  portrait  and  landscape 
photographer  must,  in  fitting  himself  for  his  profession,  study  the  arts  of  design,  drawing, 
perspective,  composition,  and,  possibly,  color. — L.  W.  SEAVEY. 

I  am  especially  interested  in  the  varying  effect  which  dark  and  light  backgrounds  have 
on  the  intensity  of  the  negative,  because  I  have  satisfied  myself  of  the  truth  of  the  theory 
as  to  the  actual  increase  of  intensity  in  the  lights  when  a  dark  background  is  used.  In 
such  cases,  there  is  comparatively  little  demand  upon  the  free  nitrate  on  the  plate  during 
development,  and  it  is,  therefore,  liberally  deposited  on  the  lights,  giving  them  an  actually 
larger  proportion  of  silver,  and  hence,  greater  intensity  than  they  could  have  had  if  a 
light  background  or  light  draperies  had  been  present,  demanding  a  large  share  of  the 
silver  deposited  during  the  development.  The  presence  of  a  dark  background  is,  in 
fact,  equivalent,  in  its  effects  on  the  lights,  to  the  addition  of  a  little  more  silver  solution 
to  the  developer.  At  first  sight  many  will  be  disposed  to  affirm  that  the  increased  bril- 
liancy of  the  light  in  pictures  with  dark  backgrounds  and  preponderance  of  dark 
draperies,  is  more  apparent  than  real,  and  that  the  appearance  of  brilliancy  is  due  to  the 
effect  of  contrast,  the  class  of  pictures  produced  by  M.  Adam  Salomon  being  possibly 
instanced  as  illustrating  this.  The  dark  background  and  preponderance  of  masses  of 
shadow  in  the  draperies  will  be  pointed  out  as  manifestly  giving,  by  contrast,  an  unusu- 
ally intense  effect  to  the  lights.  This  is,  to  a  large  extent,  undoubtedly  true ;  skilfully 
managed,  contrast  is  a  very  legitimate  source  of  brilliancy,  and  the  purity  and  intensity 
of  a  light  can  at  any  time  be  forced  by  placing  it  in  juxtaposition  with  deep  shadows  or 
dark  masses.  But  Mr.  Anderson  points  out  another  cause,  from  which  it  will  be  seen  that 
the  lights  in  such  a  case  not  only  seem  to  be  more  brilliant,  but  that  they  actually  are 
more  intense.  In  this,  as  I  have  said,  I  fully  agree  with  him.  I  remember  the  circum- 


UNDER    THE    SKYLIGHT.  125 

The  figure  is  softened  and  a  light  shadow  thrown  over  it  from  the  face 
downward,  by  a  small  square  pasteboard  screen,  covered  with  black  velvet, 
with  a  semicircle  cut  out  of  one  side.  This  is  held  in  the  hand  and  moved 
during  exposure,  covering  the  figure  from  one-third  to  one-half  of  the  time ;  the 
time  varying  with  the  light,  of  course. 

Another  method  was  suggested  by  Mr.  R.  Gillo,  viz. :  "  Provide  a  back- 
ground about  four  feet  square,  on  a  frame,  with  a  cross-piece  at  the  back,  in 

stances  which  first  called  my  attention  to  this  fact  in  the  early  years  of  the  collodion 
process.  I  was  at  the  time  in  question  taking  some  collodion  positive  portraits,  and  was 
struck  with  the  low  tone  and  general  grayness  of  the  lights  when  a  white  background 
was  used,  compared  with  the  lights  of  pictures  with  dark  backgrounds  produced  with  the 
same  chemicals,  and  under  all  the  circumstances,  except  the  change  of  background.  I 
noticed  the  fact  that  the  white  sheet  which  on  a  daguerrotype  plate  gave  a  white  back- 
ground, on  the  collodion  positive  gave  a  dull  thin  deposit,  which  was  far  from  white. 
This  satisfied  me  that  it  was  not  simply  the  effect  of  contrast,  and  after  some  reflection 
and  a  few  experiments,  I  learned  that  it  was  due  to  the  even  deposit  of  silver  in  develop- 
ment, and  the  insufficiency  in  the  quantity  of  silver  present  to  give  a  dense  deposit  where 
so  much  white  occurred.  The  continuation  of  development  and  addition  of  a  few  drops 
of  silver — a  very  rare  circunstance  in  glass  positive  work — gave  the  lacking  intensity  to 
the  whites  in  the  picture  with  a  white  background,  and  established  the  theory  of  the 
cause  to  which  Mr.  Anderson  has  referred. 

It  is  a  fortunate  circumstance  that  the  class  of  pictures  in  which  the  use  of  light  back- 
grounds is  most  imperative,  vignettes,  least  require  intensity  or  contrast,  but  is  most 
suitably  rendered  by  softness,  delicacy,  and  harmony.  It  is  also  fortunate  that  when  the 
presence  of  much  dark  drapery,  and  small  portions  of  white  or  of  a  very  light  character 
occur  in  a  subject,  the  operator  has  the  matter  somewhat  under  control.  By  using  a 
strong  developer,  he  can  lessen  the  tendency  to  aggregation  of  deposit  on  the  lights. 
The  strong  developer  will  quickly  do  its  work,  leaving  little  time  for  aggregation,  and 
will,  at  the  same  time,  throw  down  on  the  half-shadows  their  full  share  of  deposit,  and 
so  help  to  harmonize  the  tendency,  otherwise  inevitable,  to  crudeness  from  excess  of 
contrast.— G.  WHARTON  SIMPSON. 

Since  backgrounds  and  accessories  of  such  elaborate  nature  have  come  to  be  so  exten- 
sively used  in  photography,  there  follows  the  necessity  for  the  study  of  such  laws  of 
use,  beauty,  and  fitness  as  pertain  thereto. 

Experience  alone  will  not  always  give  to  the  photographer  that  nice  discrimination 
between  truthfully  artistic  effects  and  those  which  at  first  thought  seem  quite  appropriate 
and  satisfy  the  sitter.  Culture  will  do  much,  very  much ;  but  a  little  natural  endowment 
is  essential. 

Truth,  Mr.  Euskin  teaches,  is  the  first  consideration  in  art;  harmony  and  beauty  will 
follow. 

The  most  glaring  faults  of  the  average  scenic  backgrounds  lie  in  their  foreground. 
The  objects  are  nearly  always  too  small ;  trees,  especially,  are  diminutive  and  wholly 


126         WILSON'S  QUARTEK  CENTURY  IN  PHOTOGRAPHY. 

the  centre  of  which  is  a  hole  to  allow  the  horizontal  rod  of  the  head-rest  to 
pass.  It  will  be  seen  that  when  the  rest  is  placed  against  the  head  of  the 
sitter,  the  face  appears  in  the  centre  of  the  square.  There  will  be  found  no 
difficulty  in  painting  this  small  background  with  a  gradation  from  dark  on  one 
edge  to  light  on  the  other.  Lampblack  and  whiting,  with  a  little  size,  answers 
for  the  color.  When  you  have  arranged  the  sitter,  you  can  turn  this  around 
any  way  you  please — light  at  the  top  shading  into  dark  below,  or  vice  versa  ; 
or  a  diagonal  gradation,  to  suit  circumstances  and  your  own  feeling.  The 
different  eifects  thus  produced  are  astonishing.  Sometimes  the  effect  may  be 
improved  by  shielding  a  part  of  the  light  from  the  background  with  a  blind  or 
curtain.  From  the  fact  of  this  background  being  so  close  to  the  head  of  the 
sitter,  you  often  get  a  boldly  cast  shadow  from  the  head  or  shoulders,  which  is 
very  effective. 

The  standing  of  the  background  diagonally  is  also  a  plan  by  which  very 

lack  character,  both  in  bark  and  foliage ;  they  are  neither  elm,  oak,  birch,  or  apple 
trees,  so  far  as  any  of  their  natural  characteristics  are  discernible.  Perhaps  it  may  seem 
trivial  to  pay  attention  to  these  matters,  but  a  real  artist  is  he  who  either  truthfully 
imitates  nature,  or  originates  from  his  own  mind  that  which  represents  some  principle, 
thought,  or  emotion;  while  he  who  mixes  the  attributes  of  several  objects  of  nature 
neither  imitates  nor  originates. 

Photography  is  no  longer  a  trade ;  it  is  an  art.  The  last  few  years  have  witnessed 
wonderful  achievements,  and  the  next  few  will  not  fall  short  in  this  march  toward  true 
art.  And  if  photographers  could  have  the  aid  they  deserve  in  accurate,  truthfully  painted 
grounds  and  accessories,  to  what  excellence  could  they  not  attain? 

Some  photographs  which  find  their  way  into  my  hands  attest  that  even  good  accessories 
are  frequently  so  misplaced  as  to  appear  quite  absurd ;  pictures  which  otherwise  are  very 
fair,  having  proper  lighting,  easy  posing,  and  with  finish  fully  up  to  the  average,  are 
utterly  ruined  by  a  poor  choice  of  accessory  combinations.  As  an  instance,  I  recall  a 
cabinet  photograph  of  a  young  couple  whose  dress  suit  and  orange  blossoms  bespoke  a 
recent  wedding;  the  background  was  a  forest  scene,  with  a  winding  foot-path  leading  off 
into  the  distance.  The  long  "  matted  "  grass  at  their  feet  was  another  proof  of  sylvan 
surroundings.  But  the  first  thing  which  arrested  my  attention  was  the  very  plump, 
handsomely  upholstered  gallery  chair  in  which  the  groom  was  seated,  and  I  vaguely 
wondered  what  power  had  transported  this  wholesome-looking  product  of  civilization 
into  that  rural  wilderness. 

Many  people  have  an  idea  that  the  more  pieces  of  furniture  and  knickknacks  appear 
in  the  picture,  the  more  effective  it  is,  and  this  is  true,  but  "  effective  "  only  in  so  far  as 
to  render  it  a  matter  for  conjecture  which  is  the  accessory,  the  sitter  or  the  furniture. 

One  great  difficulty  under  which  the  average  photographer  labors  is  the  expense  of 
procuring  such  an  array  of  scenic  accessories,  and  the  amount  of  room  requisite  for  their 
storage ;  as  an  alternative,  therefore,  he  must  see  that  the  few  he  considers  necessary 


UNDER    THE    SKYLIGHT 


127 


FIG.  136. 


good  effects  may  be  had,  as  the  part  farthest  away  from  the  lens  will  be  in 
deepest  shadow,  and  vice  versa.  I  would  suggest,  then,  that  the  background  be 
swung  by  its  centres  in  a  framework,  with  a  pin  at  each  side  for  it  to  swing 
upon,  and  also  pins  at  the  top  and  bottom  for  the  same  purpose.  The  pins  could 
be  used  to  keep  the  background  in  place,  when  not  used  as  above.  This  plan 
would  also  enable  one  to  have  a  background  on  each  side  of  the  frame,  and  it 
could  be  quickly  changed  at  pleasure.  Of  course,  the  backgrounds  should  be 
on  the  sw6-frame,  moving  inside  the  larger.  The  latter 
should  be  mounted  as  usual  on  castors. 

47.  In  the  matter  of  usual  apparatus  the  buyer  will 
secure  the  best  information  from  the  catalogues  and  stock 
of  his  dealer. 

The  best  in  the  world  is  procurable,  with  all  wished-for 
attachments. 

There  are  a  great  many  special  appliances,  however, 
which  the  operator  can  contrive  for  himself,  and  a  few 
pages  devoted  to  them  cannot  prove  unacceptable. 

The  annexed  cut  (Fig.  136)  represents  Mr.  S.  L.  Platt's 
adjustable  rotary  eye-rest.     You  will  see  by  the  figure  that 
the  rotary  arm  will  allow  the  picture  to  be  right  side  up  anywhere  within  the 
radius  of  the  arm. 

are  of  the  best — and  the  best  are  nature's  own  work.  For  example,  instead  of  using  an 
upholstered  chair  with  a  forest  background,  take  a  holiday  trip  out  into  the  woods,  some 
day — photographers  work  hard  enough  to  earn  many  such  luxuries — and  bring  back 
enough  wild  grape-vine  and  suitable  tree-limbs  to  make  a  graceful  rustic  chair ;  then 
use  the  spare  hours  and  construct  one  for  gallery  use.  Improvise  something  that  will 
take  the  place  of  those  painted  rocks  on  castors.  Study  nature  and  the  pretty  indoor 
designs  which  are  found  in  one's  own  home,  and  those  of  the  various  friends,  and  dis- 
courage the  use  of  all  accessories  which  savor  in  the  least  of  artificiality  when  seen  in 
the  photograph. — MRS.  CLYDE  EHINGER. 

47.  Why  will  not  a  camera  that  will  make  a  whole-size  picture  from  life  make  one 
the  same  size  from  a  card  picture?  I  will  explain.  When  about  to  purchase  a  camera, 
always  bear  in  mind  that  the  size,  no  matter  what  it  is,  will  only  reproduce  a  picture  its 
original  size.  That  is  to  say,  a  half-size  camera  and  half-size  tube  will  only  reproduce 
a  picture  its  original  size,  no  matter  whether  it  be  a  card  picture  or  a  half-size  picture. 
If  you  wish  to  copy  a  whole-size  picture  to  its  original  size,  you  must  have  a  whole-size 
camera  and  lens— an  8  x  10  box  and  lens  for  an  8  x  10  picture,  and  so  on  for  the  different 
sizes.  This  plan  of  working  would  require  one  to  have  a  number  of  boxes  and  tubes, 
which  would  be  both  expensive  and  troublesome.  There  are  two  ways  to  obviate  this, 


128 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


The  plan  for  a  good  copying-board  comes  from  Mr.  W.  G.  Smith  (Fig.  137.) 
To  the  frame,  or  head-piece,  is  attached  a  cord  which  runs  in  a  groove  under- 
neath  the  bed,   and  works  with  a  thumb-screw  at   the 
end.     It  enables  one  to  get  the  picture  in  position  on  the 
ground-glass  without  removing  the  head  from  under  the 
IT! TIT  dark-cloth. 

Another  little  dodge  comes  from  Mr.  R.  Benecke  (Fig. 
138.)  The  object  is  to  see  at  one  glance  whether  a  plan, 
map,  etc.,  to  be  copied,  stands  parallel  with  the  instrument, 
It  is  nothing  but  a  straight  board  about  six  or  eight  inches 
square,  in  the  centre  of  which  a  round  stick  is  fastened 
perpendicularly.  Thus  :  Let  the  board  be  of  a  dark  color, 
and  the  stick  white.  Now  hold  it  or  hang  it  by  a  string 
in  front  of  the  drawing ;  let  the  stick  be  there  where  the 
two  diagonals  would  cross  each  other.  Next  point  your  camera  at  it.  Now  if 
you  see  in  the  centre  of  your  ground-glass  a  white  circular  spot  on  dark  ground, 

FIG.  139. 


FIG.  138. 


MM 


your  drawing-board  and  camera  stand  correct ;  if  not,  that  is,  if  you  see  the 
picture  of  this  contrivance  too  high  or  too  low,  lower  or  raise  your  instrument, 
and  shift  it  until  you  see  no  more  of  the  stick  but  a  white  spot  on  black 
ground.  Fig.  139  will  explain  it  at  once. 

viz.,  either  to  have  a  long-bellows  camera  (Fig.  141)  made  on  purpose  for  copying,  or  to 
have  a  simple  contrivance  called  a  cone  (Fig.  142)  made  to  fit  on  your  ordinary  portrait 
box.  The  camera  represented  in  Figs.  141  and  142  is  one  of  the  11  x  14  size  of  the 
American  Optical  Company's  make,  and  is  capable  of  being  drawn  out  thirty-four  inches. 
This  box,  with  a  double  whole-size  lens  attached,  will  only  make  a  11  x  14  picture  its 
original  size.  If,  now,  we  take  off  the  double  whole-size  tube  and  replace  it  with  a  whole- 
size  tube  it  will  make  a  11  x  14  copy  from  a  whole-size  original.  Again,  if  we  replace 
it  with  a  half-size  tube,  we  can  make  a  11  x  14  copy  from  a  half-size  picture.  If  now 
we  wish  to  copy  a  card  picture  to  a  11  x  14  size,  the  camera  will  not  be  long  enough, 


UNDER    THE    SKYLIGHT. 


129 


FIG.  140. 


The  novelty  of  Mr.  F.  M.  Spencer's  copying  apparatus  (Figs.   140,  143, 
146)  lies  in  the  arrangement  of  the  target  for  holding  the  picture  to  be  copied, 

and  for  adjusting  the  picture  to  the  field 
of  the  lens,  in  its  desired  position  on  the 
focussing  screen.  It  consists  of  a  slotted 
upright  of  ash,  seven  inches  wide  and 
twenty-four  inches  long,  screwed  firmly 
at  one  end  to  the  centre  of  the  end  of 
the  table;  upon  this  there  is  a  jacket, 
sliding  vertically,  to  which  the  movable 
block  of  a  wood  screw  is  attached.  This 
block  plays  vertically  in  the  three-inch 
wide  slot  in  the  upright ;  the  rigid  block 
near  the  pulley  of  the  wood  screw  is 
screwed  fast  to  the  bottom  of  the  up- 
right slotted  post.  A  strong  cord  band 
plays  upon  the  screw-pulley,  and  around 
another  pulley  near  the  opposite  end, 
and  underneath  the  table,  which  serves 
as  a  tightening  pulley  to  keep  the  band 

taut,  which,  it  will  be  observed,  is  attached  to  the  centre  of  a  bar  transverse  to 
the  table,  pivoted  at  one  end,  and  held  in  place  by  a  panel  of  heavy  wire  at  the 

and  we  must  either  have  a  longer  box  made  specially,  or  use  a  cone  as  in  Fig.  142. 
Fig.  141  is  the  camera  with  a  half-size  lens  attached,  and  is  capable  of  making  a  11  x  14 
copy  from  a  half-size  picture,  an  8  x  10  from  a  card  picture  or  medium-size  ambrotype 


FIG.  141. 


FIG.  142. 


or  daguerrotype,  or  the  whole  size  from  a  ^th  size.  Fig.  142  is  the  same  camera  with 
the  front  taken  out  and  the  cone  put  in  its  place,  and  the  same  tube  on  the  end  of  the 
cone.  The  cone  is  24  inches  long,  which  with  the  box  drawn  out  its  full  length,  gives  a 

9 


130         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

othter.  Now,  by  pulling  upon  the  cord  the  wood  screw  is  rotated,  causing  the 
jacket  upon  the  slotted  post  to  move  up  or  down,  at  the  will  of  the  operator, 

by  which  means  the  perpendicular  ad- 

FIQ.  143.  .  f , ,       .  ,        .  ,      rp, 

justment  of  the  picture  is  secured.     The 

face  of  the  jacket  facing  the  camera  has 
a  rabbetted  bar  screwed  to  the  upper, 
and  one  also  to  the  lower  end  of  it, 
forming  grooves,  in  which  the  target  (or 
easel)  slides  horizontally ;  the  target  is 
made  of  half-inch  pine,  twelve  inches 
wide,  and  eighteen  inches  long,  rabbetted 
on  the  edges  so  as  to  fit  easily  into  the 
grooves  of  the  jacket-front ;  a  piece  of 
pine  wood,  five-eighths  of  an  inch  thick 
and  one  inch  wide,  is  screwed  or  nailed 
to  each  end  of  the  target,  on  opposite 
sides,  to  prevent  warping.  Midway 
from  the  edges  of  the  target  are  two 
slots,  bevelled  on  the  back,  and  separated 
by  a  space  of  three  inches  at  the  centre, 

the  purpose  of  which  is  to  allow  the  passage  of  a  common  screw  of  wood,. 

which  is  passed  from  the  back  of  the  target  into  strips  of  hard  wood  half  an 

focal  length  of  58  inches.  This  length  will  give  a  11  x  14  picture  from  a  ^th  size  or 
even  smaller  ambrotype.  The  same  rule  holds  good  with  all  cameras.  If  a  whole-size 
box  is  the  largest  you  have,  a  quarter-size  tube  will  give  you  a  whole-size  picture  from  a 
medium  ambrotype  or  card  picture;  but  if  the  picture  to  be  copied  is  smaller  than  that, 
you  will  need  a  cone,  which,  however,  need  not  be  over  12  inches  long.  Before  con- 
cluding this  subject,  I  cannot  too  highly  recommend,  to  those  who  have  not  tried  it,  the 
use  of  the  swing-back  camera. — GEORGE  H.  FENNEMORE. 

A  convenient  copying-table  is  made  as  follows :  A,  an  ordinary  table,  having  legs  three 
feet  long,  with  a  solid  top  hinged  at  one  end.  Underneath  this  top  is  a  sliding-board  J3, 
full  length  of  top,  and  six  inches  wide,  held  by  dovetailed  pieces  screwed  to  the  top. 

Near  each  end  of  this  sliding-board  are  two  half-inch  holes,  into  which  fit  corresponding 
pins  attached  to  a  shorter  board  (7,  which  stands  at  right  angles  to  B.  Upon  this  shorter 
or  upright  piece  is  placed  the  small  blackboard,  on  which  are  fastened  the  pictures 
desired  to  be  copied.  This  is  also  made  adjustable  by  dovetailing  on  C. 

To  get  rid  of  the  granulated  appearance  of  copies  from  paper  pictures,  which  is  caused 
by  lights  and  shadows  on  the  uneven  texture  of  the  paper,  tilt  the  camera  as  shown  in 
Fig.  145,  so  that  the  light  falls  as  near  at  right  angles  as  possible. 


UNDER    THE    SKYLIGHT. 


131 


inch  thick,  one  inch  wide,  and  ten  and  a  half  inches  long,  entering  the  strips 
at  their  centre,  and  drawn  sufficiently  close  to  sink  the  head  of  the  screw  in  the 
bevels  of  the  slots  on  the  back,  but  not  to  prevent  the  sliding  of  the  screw  freely 
in  the  slots ;  the  inner  edges  of  these  strips  are  bevelled  down  to  obviate  their 
casting  shadows,  and  the  springs  that  hold  the  picture  to  be  copied  are  screwed 
at  one  end  to  the  ends  of  these  strips ;  by  this  arrangement  the  springs  and 
strips,  or  bars,  to  which  they  are  made  fast,  may  be  quickly  adjusted  at  any 
desired  angle,  to  obviate  casting  a  troublesome  shadow,  and  to  hold  the  picture. 

FIG.  144. 


Now,  to  control  the  horizontal  movement  of  the  target,  a  cord  is  made  fast  to 
screw-eyes  in  the  ends  of  the  target,  and  passed  through  other  screw-eyes  in  the 

This  tilting  is  done  by  a  device  plainly  shown  in  the  illustration,  viz.,  by  a  couple  of 
pieces  hinged  to  the  underside  of  the  table  cover,  and  resting  on  notched  pieces  fastened 
to  the  inside  of  the  rails  of  the  table. 


FIG.  145. 


FIG.  146. 


It  will  readily  be  seen  that  it  matters  not  at  what  angle  your  camera  may  be,  the 
picture  to  be  copied  will  be  parallel  to  it.  Have  a  narrow  cleat  fastened  to  the  end  of 
the  table  to  prevent  the  camera  sliding  off;  it  also  serves  as  a  guide  to  keep  it  and  the 
picture  at  right  angles  to  each  other  laterally. 

Fig.  146  represents  the  same  table  as  I  use  it  for  making  magic-lantern  slides,  porcelain 
pictures,  and  reproducing  negatives. 


132 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


edge  of  the  slotted  post,  and  at  the  bottom  of  the  table  on  each  side,  and  so  back 
under  the  table  through  another  eye  at  the  back  end  of  the  table ;  this  cord 
must  be  slack  enough  not  to  bind  the  vertical  movement  of  the  target.  Now, 
by  pulling  upon  this  slack  cord,  the  target  and  picture  are  made  to  move 
horizontally  toward  the  opposite  side.  It  will  be  seen  that  the  picture  to  be 
copied,  having  been  placed  upon  the  target  by  means  of  the  cords,  may  be 
adjusted  and  focussed  without  once  removing  the  eye  from  the  screen,  until 
both  position  and  focus  have  been  obtained ;  which,  when  many  copies  are  to 
be  made,  will  prove  a  great  saving  of  time. 

48.  An  inside  shutter  for  the  camera  is  suggested  by  Mr.  R.  A.  Hickox. 
The  slide  is  permanently  attached  to  the  inside  of  the  camera  front.  When 
placed  in  the  camera,  it  is  opened  by  pulling  the  string,  which  is  hooked  to  the 
under  edge  of  fhe  slide,  and  passes  through  a  hole  in  the  bottom  of  the  front 
of  the  box  and  the  top  of  the  camera-stand  ;  a  cloth  screen  tacked  to  the  front 
of  the  camera-stand  hides  the  position  and  movement  of  the  hand  while  making 
the  exposure.  This  arrangement  is  especially  useful  in  photographing  children, 

The  camera  is  of  course  reversed  on  the  table  this  time,  pointing  upward  and  toward 
the  light.  A  is  a  box,  which  replaces  the  sliding  blackboard  used  in  copying,  with  its 
open  side  toward  the  lens.  The  negative  is  placed  at  JB,  and  a  vignetting  diaphragm  at 
C.  The  open  side  of  the  box  being  toward  the  lens  sufficiently,  shades  the  near  side  of 
the  negative,  and  secures  the  transmission  of  all  the  light  coming  from  that  direction. 

The  upright  piece  upon  which  the  box  A  slides  has  a  large  oval  hole  cut  out  of  it  for 
this  purpose. — B.  F.  HALL. 

48.  One  of  the  best  methods  for  testing  the  correctness  of  the  focus,  is  to  take  an 
arrangement  of  this  kind  (Fig.  147) ;  D  is  a  piece  of  board,  a  foot  long  and  six  or  eight 

inches  wide,  cut  in  this  shape ;  CB  A  are  good  stout 
business  cards,  with  printing  on  them,  of  course, 
put  in  slits  at  right  angles  with  the  edge  of  the 
board,  and  the  face  of  each  card  toward  the  letters 
in  the  diagram.  This  we  place  in  front  of  the 
camera,  at  about  the  distance  we  would  make  an 
ordinary  sitting,  and  focus  on  the  middle  card; 
the  others  will  then  be  out  of  focus,  and  it  is  im- 
portant that  you  have  them  both  alike — that  is, 
taking  it  for  granted  that  the  cards  are  equidistant. 
Now  prepare  and  expose  a  straight  plate,  and  if 
the  focus  comes  the  same  as  on  the  ground-glass 
we  are  all  right,  but  if  C  is  sharper  than  B,  or  vice 
versa,  then  the  ground-glass  must  be  regulated  till 
it  is  right.— R.  J.  CHUTE. 


UNDER    THE    SKYLIGHT. 


133 


FIG.  148. 


as  the  exposure  is  made  without  attracting  their  attention.  It  is  very  simple, 
and  can  be  made  by  any  operator  who  has  any  mechanical  ingenuity.  The 
slide  is  made  of  a  little  strip  of  wood,  half  or  three-fourths  as  wide  as  the 
diameter  of  the  lens.  A  strip  of  black  silk  is  pasted  to  the  lower  edge  of  the 
slide,  and  made  fast  to  the  bottom  of  the  front.  When  the  shutter  is  up,  all 
light  is  shut  out  of  the  box ;  when  down  it  is  open.  There  is  no  use  for  a 
cap  or  cover  for  the  front  of  the  lens. 

Mr.  C.  N.  Stevens  communicates  his  method  of  making  medallion  masks  as 
follows  :  I  first  had  made  a  frame,  30  by  40  inches,  of  strips  half  an  inch  thick 
by  two  inches  wide  ;  then  a  piece  of  building-paper  was  tacked  to  the  frame, 
and  trimmed  the  same  size.  Now  lay  the  frame  on  the  floor  and  get  the  centre 
by  laying  a  straight-edge  across  from  corner  to  corner  each  way.  Make  a 
pencil-mark,  and  you  have  a  X  in  the  centre ;  now  measure  from  the  X  the 
longest  way  of  the  frame,  7J  inches  each  way,  and  drive  a  nail  through  into 
the  floor ;  now  take  a  string  and  pass  around  one 
nail,  carry  it  by  the  other  one,  and  tie  it  just  3J 
inches  beyond,  then  take  a  pencil,  put  it  inside  the 
string,  mark  around,  and  you  have  an  oval  16  by 
21 J  ;  take  a  sharp  penknife  and  cut  it  out  carefully, 
then  get  a  piece  of  bleached  muslin,  and  paste  it  on 
smooth,  cut  it  in  the  centre,  and  paste  it  on  the  op- 
posite side,  turn  the  cloth  in  and  put  it  down  smooth. 
Now  get  four  pieces,  six  feet  long  by  two  inches 
wide,  hinge  them  at  the  top,  mount  your  frame,  and 
you  are  fixed  for  making  medallion  ferrotypes. 
The  paper  will  warp  when  you  paste  on  the  cloth, 
but  never  mind,  it  will  be  all  right  when  dry. 

Mr.  F.  M.  Spencer's  curtain  stand  supplies  a 
support  for  a  curtain  that  can  be  easily  moved  and 
properly  adjusted.  The  accompanying  illustration 
(Fig.  148)  explains  itself,  being,  as  will  be  seen,  readily  adjusted  to  any  height, 
and  convenient  to  move  into  any  position.  The  arrangement  of  the  curtain  on 
the  cross-bar  is  such  as  to  cause,  it  to  hang  in  folds,  so  as  always  to  produce  a 
good  effect. 

49.  Photographs  are  as  often  defective  from  bad  focussing  as  from  any 
other  cause.  When  a  good  lens  is  perfectly  focussed,  and  the  resulting  negative 
is  printed  upon  highly  albumenized  paper,  pressed  firmly  against  it,  there 


134       WILSON'S  QUAKTEB  CENTURY  IN  PHOTOGRAPHY. 

results  a  picture  with  a  brilliant  clearness  of  outline,  which  no  engraving,  no 
artist's  sketch,  can  in  the  least  rival.  The  effect  is  extremely  beautiful.  It  by 
no  means  interferes  with  softness.  It  would  be  as  reasonable  to  say  that  a 
landscape  could  have  no  softness  with  a  clear  atmosphere,  and  that  the  best 
time  to  view  natural  scenery  is  in  foggy  weather ;  such  a  position  would  not 
be  one  whit  more  absurd  than  condemning  sharp  photographic  work  as  neces- 
sarily hard,  or  even  tending  to  be  so. 

Doubtless  much  imperfect  focussing  depends  upon  the  defective  surface  upon 
which  the  picture  is  focussed.  A  good  piece  of  ground-glass  is  not  always 
obtainable,  and  one  must  often  temporize. 

One  method  consists  in  applying  a  layer  of  starch  upon  the  plate,  which  in 
drying  leaves  a  thin  opalescent  pellicle.  The  other  consists  in  precipitating 
sulphate  of  baryta  in  a  solution  of  gelatine,  by  which  means  the  baryta 
salt  is  kept  completely  suspended  in  the  liquid.  A  plate  of  glass  coated 
with  this  opalescent  gelatine  and  allowed  to  dry,  makes  an  excellent  focussing 
surface. 

Dr.  M.  Carey  Lea  details  another  substitute  as  follows  :  "  Prepare  a  varnish 
which  should  itself  have  the  necessary  opalescence.  That  I  have  succeeded  in 
doing,  and,  thereby,  have  prepared  focussing  plates  free  from  all  tendency  to 
peel  off.  The  substance  which  I  employ  for  this  purpose  is  tartaric  acid. 

I  take  a  good  negative  varnish  made  with  alcohol,  and  saturate  it  thoroughly 
with  tartaric  acid.  It  does  not  dissolve  a  great  deal,  and  to  get  a  sufficient 
quantity  into  solution,  the  acid  must  be  finely  pulverized,  added  in  considerable 
excess,  and  the  vial  well  shaken  at  intervals  for  several  days.  It  may  then  be 
allowed  to  settle  for  a  day  or  two,  when  the  clear  liquid  is  to  be  poured  off. 

It  is  to  be  applied  precisely  in  the  same  way  as  in  varnishing  a  negative — 
that  is,  the  plate  is  to  be  gently  warmed  before  and  after  the  application  of  the 
varnish." 

50.  A  few  more  camera  contrivances  and  then  the  subject  of  actual  work 
will  be  treated. 

To  make  a  small  figure  on  a  large  plate,  Mr.  James  Mullen  directs  as  fol- 
lows :  "A  short  time  since,  having  occasion  to  make  a  small  standing  figure  on 

50.  I  can  best  explain  my  method  of  copying  statuary  in  varied  positions  on  one  plate, 
by  giving  my  first  experience.  I  had  occasion  to  make  some  card  copies  of  a  small 
marble  statue  of  the  Greek  Slave,  and  thinking  it  would  make  a  much  more  attractive 
picture  if  it  could  be  copied  in  a  variety  of  positions  on  one  card,  I  attempted  it.  I  took 


UNDER    THE    SKYLIGHT.  135 

a  14  x  17  plate,  and  my  ceiling  being  low  back  of  the  skylight,  preventing  my 
getting  the  desired  height  of  plain  ground  above  the  head  of  the  subject  with- 
out showing  the  top  of  the  background  and  ceiling,  or  finishing  in  vignette, 
which  was  not  desired,  I  finally  hit  upon  the  following  plan,  by  which  I 
accomplished  it  perfectly : 

"I  took  a  piece  of  straw  board  and  attaching  it  to  a  head-rest,  placed  it  a 
little  above  and  in  front  of  the  lens,  in  such  a  position  as  to  blend  perfectly 
with  the  background' above  the  subject's  head ;  thus  I  obtained  all  the  height 
desired.  You  will  observe  this  method  will  admit  of  graduating  the  back- 
ground, making  it  either  lighter  or  darker,  as  may  be  desired,  by  simply 
changing  the  position  of  the  board  in  front  of  the  camera. 

A  simple  means  for  producing  a  number  of  pictures  with  a  single  lens  comes 

for  the  background  a  strip  of  dark  brown  cotton-velvet,  arranging  it  so  that  the  lower 
portion  covered  the  top  and  hung  a  few  inches  over  the  edge  of  a  small  stand.  Placing 
the  image  on  the  centre  of  the  stand,  I  got  the  proper  size  and  focus  with  the  ordinary 
camera,  and  made  a  faint  mark  around  the  base  on  the  velvet,  then  moved  the  image 
to  the  right  and  left  of  the  first  position,  being  careful  that  one  position  should  not  inter- 
fere with  the  other,  and  marking  around  the  base  each  time,  that  I  might  know  just 
where  to  place  it  in  the  subsequent  operations.  I  then  prepared  and  exposed  my  plate, 
covered  the  camera,  moved  the  image  to  the  next  position,  and  exposed  again  as  before. 
On  developing  my  plate,  I  found  I  had  a  remarkably  fine  negative  of  one  object  in 
three  positions.  Almost  any  number  of  positions  may  be  obtained  in  this  way. — 
GEORGE  WILLIAM  WHITE. 

For  vignetting  in  the  camera,  I  use  the  following  device  (Fig.  149).  A  represents  the 
camera-box,  moved  to  one  side  of  the  top  of  the  stand,  in  order  to  delineate  the  other 
parts  more  easily.  B  is  a  strip  of  one-half  inch 

walnut,  of  any  proper  length,  with  a  slot  in  it  FlG*  149< 

nearly  the  whole  length.  E  is  a  piece  of  stiff 
cardboard,  cut  to  the  shape  in  the  drawing,  and 
attached  to  the  end  of  the  strip  B  by  the  screw- 
knob  D,  by  means  of  which  it  may  be  turned  at 
any  angle  desired.  The  strip  B  is  fastened  to 
one  side  of  the  top  of  the  camera-stand  by 
means  of  another  screw-knob  at  C,  on  which  it 
is  also  worked  back  and-  forth.  It  also  enables 
us  to  control  the  whole  apparatus,  and  by 
loosening  it  we  may  move  it  up  or  down,  as 
shown  by  the  dotted  lines.  If  you  wish  to 

prevent  an  abrupt  line,  work  the  card  J£back  and  forth  gently  during  exposure,  by  means 
of  the  knob  D.—G.  W.  EDMONDSON. 


186 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  150. 


FIG.  151. 


from  Mr.  Henry  W.  Brown.  (Fig.  150.)  Cut  a  piece  of  pasteboard  just  the 
size  to  fit  tight  in  the  camera,  closely  in  front  of  the 
ground-glass  or  plate-holder.  If  you  want  four  gems 
on  a  one-quarter  plate,  cut  an  oval  in  your  card  just  in 
front  of,  say,  the  lower  left  quarter  of  your  plate.  Now 
make  your  exposure,  and  turn  your  card  from  left  to 
right,  and  make  your  exposure  on  the  lower  right  quarter 

Oof  your  plate ;  now  turn  it  from  bottom  to  top,  etc.     In 
this  way,  with  one  or  more  cards,   you  can   make  as 
many  gems  on  a  plate  as  you  want  to.     It  will  be  found 
particularly  useful  in  taking  pictures  of  the  little  folks. 
Below  is  a  German  contrivance  for  making  medallion  portrait  cartes.     The 

Another  method  follows :  Fig.  151  will  show  the  arrangement  of  the  needed  apparatus, 
which  is  simple  enough,  being  only  a  box  without  a  bottom,  which  can  be  fastened  over 

the  lens  by  means  of  a  rim  of  wood  and  a  but- 
ton. The  box  has  a  hinged  lid  on  one  of  its 
sides  (this  may  be  dispensed  with),  and  is 
square  as  to  the  opening  at  the  bottom,  so 
that  it  may  be  fastened  on  the  camera  with  the 
side  opening,  pointing  either  upward  or  down- 
ward, or  to  the  side.  The  mirror,  fastened  on 
a  wooden  frame,  is  fixed  at  an  .angle  of  45  de- 
grees with  the  front  of  the  camera.  The 
mirror  must  have  a  perfectly  plane  surface, 
and  may  be  made  of  speculum  metal,  care- 
fully polished,  or  of  glass  silvered  on  Its  sur- 
face. A  convenient  general  size  for  the  mirror 
is  4  x  3  inches.  At  the  upper  part  of  the  box 
may  be  a  small  door  for  insertion  of  dia- 
phragms. It  is  not  at  all  difficult  to  silver 
the  mirror,  several  methods  having  been  pub- 
lished in  the  books  on  photography.  There 
should  be  no  difficulty  in  using  this  arrange- 
ment for  ferrotypes,  as  speculum  mirrors  were 
commonly  used  by  daguerrotypists  for  the 
same  purpose.  The  same  contrivance  may  be 
used  for  copying  articles  on  the  ground  which 
cannot,  without  much  labor,  be  fastened  to  a 
plane  board — a  lot  of  shells,  for  example,  or 
fruit,  or  an  engraving  which  you  do  not  wish 

to  mutilate,  etc.     The  advantages  of  copying  on  the  ground  by  means  of  the  mirror  are 
really  very  considerable,  as  you  will  readily  understand. 


B 


A,  mirror  supported  on  wooden  frame. 

B,  door  to  mirror-box. 

C,  small  door  to  change  diaphragms. 

D  D,  screws  to  slide  mirror  up  or  down  slots. 

E,  button  to  fasten  mirror-box  on  front  of  camera. 


UNDER    THE    SKYLIGHT. 


137 


FIG.  152. 


camera  (Figs.  152,  1  and  2)  consists  mainly  of  a  draw-box,  with  frame,  b  6, 
for  the  plateholder  and  ground-glass.  A  grooved  shaft  (Fig.  152,  2),  D,  D  is  at- 
tached to  the  frame  b  b.  With  this  shaft 
two  pinion-wheels,  c  c,  are  connected, 
which  work  into  the  racks,  fastened  to 
the  plateholders.  If  the  shaft  is  turned 
by  the  buttons,  o,  the  plateholder  will 
be  raised  or  lowered  in  any  required 
position,  and  their  position  retained  by 
the  ratchet  and  wheel,  S  (Fig.  152,  2). 
Both  the  pinions,  c  c,  are  movable  on 
the  shaft  D.  The  plateholder,  K  (Fig. 
152,  3)  may  be  placed  in  any  position 
by  such  an  arrangement.  To  make 

different  exposures  in  a  required  order,  the  back  of  the  plateholder,  Kj  is  pro- 
vided with  a  corresponding  pattern,  R  (Fig.  152,  3),  and  the  plateholder  moved 
by  the  racks  and  pinions,  until  the  pin  (index),  p,  which  is  fastened  to  the 
middle  of  the  shaft,  D  D,  and  precisely  in  the  optical  axis  of  the  lens,  cor- 
responds with  a  required  point  of  the  pattern ;  then  the  plate  is  exposed,  shut, 
the  plateholder  moved  to  another  point  corresponding  with  the  pattern  and 
again  exposed,  etc. 

A  novel  baby  shutter  comes  from  Mr.  G.  W.  Coddington.     Fig.  153  shows 
a  front  view  of  the  block  and  tube.     The  block  is  about  one  and  a  half  inches 

FIG.  154. 


thick,  or  as  thick  as  the  length  of  the  movement  given  by  the  rack  in  focussing 
the  instrument,  so  that  the  back  lenses  shall  not  go  clear  through  the  block. 
At  any  lowermost  corner  through  the  block  is  passed  a  rod  or  wire  one-eighth 


138 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


of  an  inch  thick,  with  a  shoulder  or  flange  soldered  on  it  where  it  enters  the 
wood,  to  keep  it  from  playing  backward  in  the  block.  The  wire  is  bent  at 
right  angles,  so  as  to  form  a  lever  to  operate  the  shutter  behind  the  tube. 

Fig.  1^4  represents  the  back  or  shutter,  which  is  soldered  fast  to  the  opposite 
end  of  the  wire  forming  the  lever,  and  is  made  of  sheet-iron  or  zinc.  Over 
this  is  passed  a  strap  of  sheet  zinc,  which  is  secured  by  two  screws  at  the  ends, 
to  keep  the  shutter  close  up  to  the  face  of  the  wood  block,  and  excludes  all 
light  when  closed  from  passing  through  the  lenses.  The  shutter  being  slightly 
larger  than  the  hole  in  the  block,  the  two  screws  that  hold  the  strap  at  the  end 
act  as  stoppers  to  the  shutter  in  opening  and  closing  the  tube  in  making  an 
exposure.  Fig.  1 54  shows  the  shutter  partly  open,  with  the  knob  on  the  lever 
projecting  at  the  side.  As  the  shutter  is  always  closed  after  making  an  ex- 
posure, it  keeps  out  all  dust  and  dirt  from  settling  on  the  back  lenses. 

Mr.  Frank  Thomas  has  devised  a  very  useful  hood  for  protecting  the  lens 
from  extraneous  light,  and  for  convenience  in  making  the  exposure. 

The  nature  of  it  will  be  seen  by  reference  to  the  accompanying  cuts  (Figs. 
1 55  and  1 56),  the  first  being  a  front  view  and  the  next  a  side  view.  It  is  so 

FIG.  156. 


constructed  that  the  rack  and  pinion  of  the  lens  and  the  central  stops  may  be 
used  without  hindrance,  and  without  removing  the  hood  from  the  lens.  The 
hood,  as  is  seen,  is  supplied  with  a  shutter,  which  is  simply  hinged  to  it,  and  a 
rubber  band  attached  to  it,  which  acts  as  a  spring. 

Mr.  Thomas  gives  tfie  following  directions  for  making  the  hood,  which  will 
enable  almost  anyone  to  procure  its  advantages  at  little  cost : 

Make  the  hood  to  fit  the  back  part  of  the  lens,  and  about  one  inch  longer 
than  the  lens.  When  it  is  run  out  then  take  off  the  front  part  of  the  lens  and 
slip  your  hood  on,  and  replace  the  front,  when  it  is  ready  and  always  on  the  lens. 


UNDER    THE    SKYLIGHT. 


139 


FIG.  157. 


It  gives  you  free  access  to  the  stops  and  ratchet,  allowing  you  to  focus  as 
usual.  For  a  J  tube,  which  is  2J  inches  in  diameter,  the  hood  should  be  5 
inches  in  diameter,  and  for  larger  lenses  in  the  same  proportion. 

There  is  a  good  deal  of  inquiry  as  to  the  means  6y  which  ferrotypes  are 
made  non-reversed — i.  e.,  so  that  the  figure  will  appear  upon  the  plate  as  it  is 
in  nature.  While  this  class  of  picture  has 
only  the  one  advantage  of  showing  the 
figure  non-reversed,  there  are  certain  draw- 
backs in  making  which  are  hardly  com- 
pensated for  by  the  advantage  spoken  of. 

In  the  first  place,  a  costly  prism  must 
be  obtained,  with  which  to  invert  the 
image  as  it  passes  through  the  lens  to  the 
plate.  A  very  quick- working  lens  must 
also  be  used.  The  prisms  alluded  to  are 
arranged  as  shown  in  Fig.  157. 

The  idea  of  making  several  pictures 
simultaneously  with  a  single  lens  was 
worked  upon  considerably  a  long  time  ago 
by  Mr.  D.  "W.  S.  Rawson,  who  has  since  died.  As  a  first  result,  he  gave  us  his 
multiplying  reflector,  which  consisted  of  a  group  of  fourteen  tiny  mirrors  the 
images  on  which  were  copied  with  a  single  lens.  The  amount  of  care  and  skill 
required  to  adjust  the  mirrors,  and  the  loss  of  light  attendant  upon  their  use, 
were  objections  to  the  plan.  These  objections  Mr.  Rawson  claimed  to  have 
overcome,  'by  the  use  of  direct  light  bent  out  of  a  straight  line  with  the  sec- 
tional parts  of  a  concave  lens,  arranged  as  follows : 

Fig.  158  represents,  first,  a  concave  lens,  which  may  be  cut  into  two,  four, 
or  more  pieces,  and  the  position  of  each  section  exactly  reversed,  as  shown  by 

a  a ;  now  the  pencil  of  light  from 
the  subject  S,  falling  upon  a  a,  is 
refracted  so  as  to  cross  at  F,  at 
which  point  the  camera  lens  is 
placed,  when  the  images  s  s  will 
be  formed  on   the  object-glass; 
the  number  of  images  thus  pro- 
duced will  correspond  with  the  number  of  sections  into  which  the  lens  is  cut. 
A  four-inch  diameter  concave  lens  may  be  cut  into  four  parts,  each  forming 


FIG.  158. 


140 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


a  square  of  about  one  and  a  half  inches ;  or  plain  wedge-shaped  lenses,  with  a 
refractive  power  of  about  ten  degrees,  may  be  used.  These  lenses  or  sections 
are  mounted  in  a  frame  in  the  position  described,  placed  in  front  of  the  camera, 
on  a  board.  No  other 'adjustment  is  required,  except  to  point  the  instrument 
to  the  subject,  and  focus  in  the  usual  way.  The  size  of  the  picture  is  varied, 
by  altering  the  distance  between  the  multiplier  and  the  camera  lens. 

The  position  of  the  subject,  multiplier,  and  camera  are  shown  in  Fig.  159. 

The  arrangement  of  the  four  sections  proves  the  most  practical,  whereby  four 
pictures  are  made  at  one  exposure ;  a  greater  number  may  be  made  by  the  use 
of  an  ingenious  plate-holder,  with  which  four  exposures  secure  sixteen  small 


FIG.  159. 


FIG.  160. 


_B 


pictures  on  the  plate.  (Fig.  160.)  A  is  a  holder,  opening  from  the  front  instead 
of  the  back.  In  the  middle  of  the  door  is  an  opening  of  one-quarter  the  size  of 
a  one-quarter  plate.  The  plate-block  C  is  of  the  size  of  a  one-quarter  plate,  and 
the  inside  of  the  holder  is  of  a  size  to  allow  it  to  move  one-half  its  length 
vertically  and  laterally,  by  which  means  each  quarter  of  the  plate-block  may 
be  brought  under  the  opening  Z),  when  the  door  is  closed  ;  the  plate  is  fastened 
to  the  plate-block  by  slipping  it  up  through  two  iron-wire  clasps  at  the  top, 
and  down  into  two  similar  ones  at  the  bottom.  When  the  plate  is  fastened  to 
the  block,  the  door  is  closed,  and  the  opening  is  covered  with  the  slide  F,  which 
slips  out  through  a  slot  in  the  side  of  the  frame,  that  it  may  be  opened  and 
closed  while  the  holder  is  in  the  camera.  The  plate-block  is  attached  to  the 
knob  on  the  back,  shown  at  B,  and  the  screw  or  rivet  that  connects  them  works 
freely  in  the  slots  in  the  back  of  the  holder ;  when  the  holder  is  placed  in  the 
camera,  the  knob  is  moved  around  to  the  top  right-hand  end  of  the  slots,  when 
the  first  exposure  is  made ;  it  is  then  moved  to  F,  where  a  notch  prevents  its 
falling,  and  so  on  around  to  G  and  H. 


CHAPTER   IX. 

THE   APPLICATION   OF   ART   PRINCIPLES. 

51.  IN  the  first  lesson  of  Wilson's  Photographies,  I  devoted  seventy-six  pages 
to  the  treatment  of  the  subject. 

.  Following  the  best  of  instructors  in  art,  John  Burnet,  I  tried  to  make  plain 
the  principles  of  art,  and  to  exemplify  them  by  means  of  words  and  about  fifty 
illustrations. 

I  began  with  "  lines,"  "  circles/'  "  angles,"  and  "  perspective ; "  then  the 
subject  of  light  and  shade  was  pursued,  and  followed  by  an  explanation  of  the 
various  forms  of  composition  adopted  by  all  good  painters  in  the  production  of 
their  works. 

These  were  the  outer  lines  of  thought.  They  were  seconded  by  considerable 
attention  given  to  the  inner  lines,  such  as  "  breadth,"  "  harmony,"  and  "  relief." 

The  various  points  were  practically  illustrated  by -numerous  diagrams  and 
engravings  from  famous  paintings  of  "  old  masters." 

The  student  was  thus  started  on  the  way,  and  then  the  subject  was  dropped, 
lest  my  desire  to  interest  him  in  art  should  be  defeated  by  overwhelming  him. 

But  now,  I  propose  to  lead  him  further  into  the  mysteries,  depths,  and 
delights  of  art's  enchanting  principles. 

And  for  illustrations,  this  time,  I  shall  use  only  engravings  from  the  paintings 
of  some  of  our  best  modern  painters. 

Let  us  begin. 

51.  It  must,  of  necessity,  be,  that  even  works  of  genius  like  every  other  effect,  as  they 
must  have  their  cause,  must  likewise  have  their  rules ;  it  cannot  be  by  chance  that  excel- 
lences are  produced  with  any  constancy  or  any  certainty,  for  this  is  not  the  nature  of 
chance ;  but  the  rules  by  which  men  of  extraordinary  parts  and  such  as  are  called  men 
of  genius  work,  are  either  such  as  they  discover  by  their  own  peculiar  observations,  or 
of  such  a  nice  texture  as  not  easily  to  admit  being  expressed  in  words ;  especially  as 
artists  are  not  very  frequently  skilful  in  that  mode  of  communicating  ideas.  Unsub- 
stantial, however,  as  these  rules  may  seem,  and  difficult  as  it  may  be  to  convey  them  in 
writing,  they  are  still  seen  and  felt  in  the  mind  of  the  artist ;  and  he  works  from  them 
with  as  much  certainty  as  if  they  were  embodied,  as  I  may  say,  upon  paper.  It  is  true 
these  refined  principles  cannot  be  always  made  palpable,  like  the  more  gross  rules  of  art; 

(141) 


142        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

52.  Once  the  principles  of  art  are  fairly  understood,  the  faculty  of  artistic 
sight  should  be  acquired. 

By  that  I  mean  the  ability  to  discern  not  only  the  proper  pose  and  balance 
of  the  lines,  but  every  tint  and  gradation  of  light  and  shade  on  the  face. 

This  faculty  of  seeing  is  only  acquired  by  close  observation  and  careful  study. 
Anyone  may  observe  the  lights  and  shadows  of  brilliant  sunshine,  such  as  are 
produced  in  nature  everywhere,  especially,  as  we  have  all  seen,  when  the  shadow 
of  a  great  cloud  goes  sweeping  over  the  landscape ;  it  requires  no  particular 
cultivation  of  sight  to  see  these,  but  in  the  studio,  and  on  the  human  face  where 
the  soft  light  is  blended  with  the  flesh  tints  and  forms  of  features,  the  faculty 
of  seeing  must  be  cultivated. 

We  all  recognize  the  conditions  necessary  to  success  in  the  use  of  chemicals, 
and  are  careful  to  work  them  according  to  certain  rules,  but  no  condition  of 
chemicals,  however  carefully  manipulated,  will  compensate  for  a  badly  lighted 
model ;  hence  it  is  necessary  that  as  strict  an  observance  of  rules  in  lighting 
should  be  practised  as  in  the  management  of  the  chemicals. 

Mr.  Robinson,  in  his  excellent  work,  Pictorial  Effect  in  Photography,  says 
on  the  subject  of  "  artistic  eyesight : "  "  There  is  a  tendency  among  young 
artists  to  despise  rules,  and  to  trust  to  instinct  and  feeling  for  art ;  but  it  is 
not  only  well  to  do  right,  even  if  that  were  possible,  by  instinct  alone,  but  it  is 
also  pleasant  to  know  you  are  doing  right." 

Thus  it  is  with  the  subject  before  us ;  we  may  have,  or  acquire,  a  sort  of 
instinctive  faculty  of  seeing  what  we  do,  but  in  that  case  it  is  guess-work  in  a 

yet  it  does  not  follow,  but  that  the  mind  may  be  put  in  such  a  train  that  it  shall  perceive 
by  a  kind  of  scientific  sense,  that  propriety  which  words,  particularly  words  of  unprac- 
tised writers  such  as  we  are,  can  but  very  feebly  suggest. — SIR  JOSHUA  EEYNOLDS. 

52.  As  the  best  practical  hints  are  derived  from  accidental  combinations  in  nature, 
whose  sudden  changes  prevent  the  possibility  of  sketching,  the  mind  ought  to  be  trained 
to  the  most  regular  and  even  mechanical  mode  of  arranging  the  ideas ;  that  in  an  instant 
we  may  be  able  to  determine  whether  the  effects,  which  we  perceive,  depend  upon  a  par- 
ticular form,  or  upon  particular  arrangement  of  the  light  and  shade.  By  thus  tracing 
effects  to  their  proper  causes,  we  secure  the  principal  points  as  a  sort  of  short-hand  notes 
to  guide  and  assist  the  memory.  This  practice  will  also  open  a  road  of  communication 
between  the  eye  and  the  operations  of  the  mind,  which  neither  a  hasty  sketch  nor  the 
most  learned  dissertation  can,  separately,  produce.  At  first  it  may  seem  more  difficult 
than  it  really  is ;  but  a  few  trials  will  convince  the  student  of  its  practicability,  especially 
as  the  effects  that  strike  him  to  be  the  most  pictorial  are  generally  the  most  simple. — 
JOHN  BURNET. 


THE    APPLICATION    OF    ART    PRINCIPLES. 


143 


FIG.  161. 


great  measure ;  the  uneducated  artist  makes  his  movements  in  a  sort  of  experi- 
mental manner ;  he  looks  this  way  and  then  that,  hesitates  in  one  motion,  and 
then  another,  till  finally  he  takes  a  grand 
survey,  and  guesses  it  will  come  out  all 
right.  Now  this  guessing  it  will  come  out 
all  right  is  a  delusion,  and  almost  inevi- 
tably results  in  failure.  The  only  surety 
that  a  sitting  will  come  out  all  right,  is  to 
see  that  it  is  right  before  the  camera. 

And  this  desirable  faculty  is  as  needful 
in  portraiture  as  it  is  in  outdoor  photog- 
raphy. 

53.  The  beauty  of  a  picture  depends 
so  much  upon  its  treatment.  For  example, 
a  beautiful  face  may  be  made  to  look  flat, 
uneven,  and  unamiable  by  photography,  if 
under  a  full  front  light.  An  architectural 
ruin  may  be  made  all  the  more  a  ruin,  and 
its  picturesqueuess  utterly  destroyed,  by 
flooding  it  with  light. 

Let  us  see  these  points  demonstrated. 
The  drawing  (Fig.  161)  is  by  Mr.  W.  R. 
Donovan,  from  a  bust  of  Thomas  Le  Clear,  N.A.  It  is  a  fine  example  of  the 

53.  The  application  of  photography  to  portraiture  has  reformed,  and  almost  revolu- 
tionized, that  art  throughout  the  world ;  yet  ninety-nine  out  of  every  hundred  photo- 
graphic portraits  are  the  most  abominable  things  ever  produced  by  any  art,  and  the 
originals  of  them  may  often  truly  say,  with  the  old  Scotch  lady  who  saw  her  own  por- 
trait for  the  first  time :  "  It 's  a  humbling  sicht ;  it 's  indeed  a  sair  sicht." 

Photography  is  a  noble  profession,  although  it  is  a  mean  trade.  Photography  has 
hitherto  been  a  refuge  for  the  destitute, 

"  A  mart  where  quacks  of  every  kind  resort, 
The  bankrupt's  refuge  and  the  blockhead's  forte." 

The  photographer  has  not  often  the  advantage,  enjoyed  by  the  painter,  of  making  the 
acquaintance  of  his  sitter  before  he  takes  the  portrait.  He  often  sees  him  for  the  first 
time  as  he  enters  his  studio,  and  has  done  with  him  in  a  short  quarter  of  an  hour.  It 
requires  great  perception  of  character  and  great  fertility  of  resource  to  enable  him  to 
determine  at  once,  and  at  a  glance,  what  is  best  to  be  done,  what  expression  he  should 
endeavor  to  call  up,  and  what  position  would  best  suit  his  sitter. — H.  P.  EOBINSON. 


144 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  162. 


judicious  management  of  light  and  shade.     The  peaceful,  benign  look  of  the  face 

of  the  gifted  teacher  in  art  could  all  have  been  destroyed  by  simply  changing 

the  main   light  to  the   front. 

From  one  of  Mr.  L.  de  For- 
rest's paintings  of  the  ruins  of 
Gertassy,  on  the  Nile,  a  draw- 
ing has  been  made  to  show 
how  all  the  roundness  of  the 
columns,  the  rich  details  of 
the  capitals,  the  mysterious 
hieroglyphics,  and  the  light 
and  shade  of  the  wonderful 
cornice  are  aBsthetically  ruined 
by  bad  lighting  (Fig.  162). 
Moreover,  the  rich  ruins  round 
about  have  no  chance  to  play 
their  part  in  a  choice  composi- 
tion, because  the  artist  chose 
his  study  at  the  wrong  hour 
of  the  day  for  the  best  effects. 
I  once  did  likewise  and  could 
be  accused  of  committing  an 

unpardonable  blunder,  were  it  not  that  I  purposely  chose  such  a  light  that  I 

might  procure  a  "  moonlight  effect "  for  my  lantern. 

54.  Otherwise  I  should   have  treated  my  subject   after  the  style  of  the 

54.  "Almost  every  one  has  seen  examples  of  these  transparencies  in  biscuit  ware  which 
produce  the  effect,  when  hung  up  at  a  window,  of  a  drawing  in  light  and  shade.  Such 
effect  is  caused  entirely  by  the  varying  thickness  of  the  plate,  which  is  so  moulded  as  to 
be  exceedingly  thin  in  the  highest  lights,  and  very  thick  in  the  extreme  darks — i.  e.,  the 
picture  is  made  up  of  gradations  of  light  and  shade.  Just  the  same  is  the  case  with  the 
photographic  negative.  It  is  made  up  of  varied  thicknesses  of  a  film  which  is  the  pro- 
duct of  sundry  chemical  mixtures  that  have  first  been  rendered  sensitive  to  light,  and 
then,  after  submission  to  the  action  of  the  light,  exposed  to  the  influence  of  other  chemi- 
cals until  the  image  is  developed.  Unlike  the  biscuit-ware  picture,  however,  which 
gives  you  the  effects  of  black  and  white  as  they  are  in  nature,  our  photographic  negative 
is  reversed — i.  e.,  the  dark  parts  are  white,  and  vice  versd.  Therefore,  in  order  to  secure 
an  approach  to  nature,  we  must  place  the  negative  on  paper  or  other  material  sensitive 
to  light,  and  expose  them  together  to  the  sun,  when  we  have  a  resulting  image  on  the 
paper  the  reverse  of  that  on  the  negative.  This  is  fugitive,  however,  and  would  soon  be 


THE    APPLICATION    OF    ART    PRINCIPLES. 


145 


FIG.  103. 


''  Temple  of  Paesturn,"  by  Mr.  Jasper  F.  Cropsey  (Fig.  163).  In  nature  this 
ruined  temple  is  not  nearly  so  picturesque  as  the  lofty  pile  at  Gertassy,  and  yet 
how  much  more  so  it  has 
l>een  made  to  appear,  by 
correct  lighting.  The  one 
recalls  our  historical  memo- 
ries of  the  ancient  Greek 
cities  on  the  Gulf  of  Saler- 
no, celebrated  by  the  Latin 
poets,  while  the  other  scarce- 
ly attracts  a  passing  thought, 
let  alone  our  careful  study. 

55.  Having  acquired  the 
ability  to  see  things  in  their 
best  light,  the  student  must  exercise   his  ability  by  permitting  it  to  mould 
his  tastes  and  to  guide  him  in  his  choice  of  subject. 

A  friend  has  truly  said :  "  The  great  requisite  for  taste  is  simplicity.  Now, 
by  simplicity,  don't  understand  tameness.  Tameness  is  always  an  indication 
of  poverty  of  resource.  Simplicity  is  best  expressed  by  temperance,  because 
taste  will  venture  much,  sometimes  very  much  that  is  not  quite  compatible 
with  conservatism,  but  this  venture  is  always  attended  with  success,  because  the 
bounds  of  temperance  are  never  overstepped.  Good  taste  never  seeks  merely 
to  astonish- — this  is  the  province  of  sensationalism.  Violent  lighting,  bizarre 
posing,  and  affected  composition  are  not  the  material  with  which  it  constructs 
that  which  is  chaste  and  beautiful.  Taste  does  not  search  in  every  corner  of 
the  globe  to  find  something  new.  No ;  it  is  content  with  the  material  which 
its  own  age  and  generation  supplies.  It  requires  far  less  ability  to  invent 
something,  the  indigest  of  the  fancy,  something  which  the  world  has  never 
seen  before,  and  which  perhaps  the  world  will  be  sorry  that  it  has  seen,  than 

discolored  and  destroyed  by  exposure  to  the  light,  were  it  not  submitted  to  the  other 
chemical  processes  of '  toning'  and  '  fixing.'  Before  it  is  finished,  the  smallest  photograph 
must  pass  through  some  thirty-two  operations." 

55.  I  am  certain  that  what  we  require  is  more  study  of  art-rules  and  principles,  so  that 
there  shall  be  more  intelligent  working  and  less  dependence  upon  chance  for  success. 
And  by  study  I  do  not  mean  wholly  the  study  of  books  and  treatises  upon  art,  but  let 
each  study  the  works  as  well  as  the  writings  of  other  masters,  and  reap  the  advantages 
to  be  drawn  from  imitating  their  examples.  In  union  is  strength,  and  the  strength 
comes  to  each  individual  by  the  union  because  each  has  access  to  all  the  knowledge  pos- 

10 


146        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

to  select  with  taste  from  the  great  storehouse  of  nature's  beauties.  It  if; 
sometimes  argued  that  fashion  controls  taste,  but  good  taste  never  finds 
any  obstacle  in  the  most  arbitrary  dictates  of  fashion,  because  it  is  superior 
to  them." 

Do  not  think,  however,  that  taste  despises  all  rules.  The  indolent  photog- 
rapher, no  matter  how  much  of  inherent  talent  he  may  have  in  matters  of 
taste,  will  find  his  vanity  a  poor  prop  to  depend  upon  for  judgment.  If 
genius  alone  discovers  laws,  surely  she  will  not  despise  their  value.  Genius  is 
never  lawless  either  in  science  or  art.  Yet  she  never  obeys  the  letter  but  the 
spirit,  which  quickens  to  greatness  of  result. 

FIG.  161. 


"The  Pursuit  of  Knowledge  under  Difficulties"  (Fig.  164),  by  Wordsworth 
Thompson,  N.A.,  supplies  an  apt  illustration  right  here  of  how  individuals 
vary  in  their  tastes. 

sessed  by  those  with  whom  he  is  united.     No  one  person,  however  much  of  genius  he 
may  possess,  can  arrive  at  any  great  degree  of  excellence  independently  of  others. 

When  the  art  was  in  its  infancy,  the  power  to  make  a  likeness  was  thought  to  be  some- 
thing wonderful,  and  the  discoverer  was  justly  regarded  as  a  genius;  but  he  would  him- 
self be  greatly  astonished  at  the  perfection  to  which  his  discovery  has  been  brought  at 
the  present  time.  Yet  no  one  has  gone  very  far  at  once.  The  first  who  gave  the  hint 
did  not  know  how  to  pursue  it  methodically.  He  worked  as  far  as  he  was  able,  and 
others  availing  themselves  of  his  experience  have  pursued  it  further.  In  fact,  our  only 
road  to  success  is  in  imitating  others  and  building  upon  the  foundation  they  have  laid. 


THE    APPLICATION    OF    ART    PRINCIPLES.  147 

There  are  people  whose  only  inbred  principle  seems  to  be  to  oppose — to  act 
"contrary"  as  the  ecclesiastical  donkey  in  our  illustration  appears  to  do.  But 
there  are  more  who  will  pursue  and  obtain  knowledge  upon  artistic  principles, 
no  matter  what  difficulties  oppose  them,  like  the  studious  monk  whom  the 
donkey  would  lead.  Such  persons  are  the  ones  who  usually  have  taste  and  the 
understanding  to  exercise  it. 

56.  Do  not  understand  that  the  photographer  should  be  a  slave  to  method, 
or  make  pictures  by  the  rule  of  three.  Let  him  use  his  own  selective  ability, 
and  if  the  conception  dawns  upon  him  that  his  picture  may  be  made  more 
beautiful — a  group,  for  example,  by  disobeying  the  rule  of  pyramidal  construc- 
tion— let  him  regard  it  as  an  inspiration  and  follow  whither  it  leads  him.  He 
can  trust  himself  if  he  is  a  student  of  art.  And  yet,  he  should  never  set  out 
with  the  intention  of  violating  all  the  set  rules  in  the  belief  that  he  will  pro- 
duce something  effective. 

I  am  myself  an  imitator,  and  am  free  to  confess  that  I  have  borrowed  much  from  such 
men  as  Kurtz  and  Notman  and  Kyder  and  Eocher,  and  many  other  shining  lights  in  our 
profession.  They,  too,  have  borrowed  from  still  others ;  and  thus,  by  imitation  and 
study,  is  progress  made.  I  would  not  be  understood  as  meaning  imitation  in  its  literal 
sense,  or  simply  the  copying  of  the  productions  of  others,  but  to  avail  ourselves  of  the 
advantages  that  may  be  drawn  from  any  and  every  source  within  our  reach. 

If  we  exclude  from  our  work  everything  that  is  not  wholly  and  entirely  our  own,  and 
make  ourselves  the  beginning  and  ending  of  all  excellence,  asking  no  instructions  from 
others,  and  seeking  to  convey  none  to  them,  we  shall  throw  away  all  the  experience  of 
our  predecessors,  and  will  soon  find  ourselves  distanced  by  those  whose  egotism  has  not 
led  them  into  such  folly.— J.  H.  KENT. 

56.  There  will  always  be  two  factions  in  the  artistic  camp.  The  idealists  and  the 
realists  are  always  at  war.  But,  in  this  country,  the  realists  now  have  the  best  of  it,  and 
the  majority  wins.  Creative  art,  in  its  highest  conventional  sense — that  is,  in  the  sense 
of  working  through  pure  imagination  and  fancy,  does  not  belong  among  us.  Repro- 
ductive art,  in  the  sense  of  depicting  human  life  and  nature  as  they  exist,  is  the  founda- 
tion of  the  modern  American  art-idea.  Photography  is  simply  a  form  of  reproductive 
art.  Realism  and  reproduction  are  one — with  the  difference  of  the  informing  spirit  of 
intellect  and  feeling,  which  in  some  subtle,  indefinable  way  raises  the  artistic  above  the 
mechanical.  This  difference  holds  good  in  literature  no  less  than  in  art.  Flaubert's 
"  Madame  Bovary  "  is  a  magnificent  piece  of  realism,  while  the  New  York  Herald  contains 
every  day  examples  of  excellent  reproductive  writing. 

Photography  is,  however,  no  less  realistic  than  reproductive,  and  the  barriers  between 
modern  art  and  modern  photography  are  every  year  being  broken  down.  A  photographer 
may  be  an  artist  or  an  artist  may  be  merely  a  photographer,  in  the  ordinary  trade  mean- 
ing of  the  word.  A  man  of  genius  does  not  trouble  himself  about  methods  or  vehicles 
of  expression,  and  he  will  accomplish  as  much  with  one  set  of  tools  as  another.  He  will 


148 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


In  the  "Testy  Old  Squire's  Complaint"  (Fig.  165),  by  Mr.  George  H. 
Story,  we  find  a  fine  illustration  of  our  last  points.     It  happens  to  be  a  literal 

illustration  of  the  taste 
of  the  small  boy  who 
stands  on  the  left.  The 
arrangement  of  the 
figures  is  effective  and 
natural ;  the  lighting 
is  carefully  artistic  and 
the  sketch  makes  its 
story  easy  to  under- 
stand, without  very 
much  telling. 

The  apples   on   the 
floor,  to  which  the  en- 
raged squire  is  point- 
ing with  his  cane,  have  been  purloined  by  the  boy  from  the  squire's  orchard. 
And  as  it  is  probably  not  the  first  offence,  the  parental  home  has  been  invaded 
to  make  complaint. 

The  father,  tilted  back  in  his  chair,  seems  to  be  saying,  "  Well,  what  are 
you  going  to  do  about  it  ?"  The  woman,  with  her  hand  on  the  door-latch, 

do  more  with  the  camera  than  a  man  of  mediocre  ability  will  accomplish  with  all  the 
color-tubes,  palettes,  and  brushes  in  the  world.  Therefore  let  photography  take  its  place 
among  us  as  one  more  recognized  and  legitimate  form  of  artistic  expression,  equal  in 
value  to  any  of  the  other  known  and  accepted  vehicles. — CHARLOTTE  A  DAMS. 

The  two  gravest,  and,  it  must  be  admitted,  most  just  charges  brought  against  portrait 
photography,  are  these:  1.  It  gives  only  the  outward  appearance  of  the  man,  a  map  of 
the  face,  as  it  were,  as  the  constraint  of  the  head-rest,  and  the  rigidity  of  the  muscles 
resulting  from  the  necessity  of  keeping  perfectly  still  while  the  exposure  continues, 
deadens  the  expression.  2.  Its  almost  mathematical  exactness  and  sharpness,  its  undue 
accentuation  of  light  and  shade,  and  the  consequent  lack  of  unity  and  tone,  deprive  it  of 
those  artistic  qualities  which  are  the  charm  of  the  work  of  the  true  artist. 

The  first  objection  has  quite  lately  been  removed  to  a  great  extent  by  the  introduction 
of  new  processes,  which  have  shortened  the  time  of  exposure  very  considerably,  and  I 
shall  not,  therefore,  dwell  upon  this  point  at  present. 

The  second  difficulty  has  engaged  the  attention  of  artistic  photographers  for  many 
years,  and  quite  a  number  of  attempts,  more  or  less  ingenious,  have  been  made  to  over- 
come it.  I  say,  advisedly,  "artistic  photographers,"  for  there  are  at  least  two  other 
varieties  besides :  the  handicraftsman,  or,  possibly,  more  correctly  speaking,  the  scientific 


THE    APPLICATION    OF    ART    PRINCIPLES.  149 

looks  defiance  at  the  complainant  and  seems  about  to  open  a  way  of  escape  for 
the  defendant,  while  the  other  members  of  the  family  are  variously  posed 
as  impartial  listeners. 

The  entire  picture  is  full  of  naturalness,  and  with  the  rapid  plates  of  to-day 
would  not  be  impossible  for  photography  to  repeat.  We  can  all  see  that  the 
painter  has  been  swayed  by  the  rules  of  art,  and  yet  his  taste  has  been  led  by 
Nature. 

57.  If  we  take  Nature  as  our  guide,  and  exercise  the  gifts  which  have  been 
imparted  to  us,  we  shall  advance  much  more  rapidly  towards  the  power  of 
good  judgment  and  good  taste  than  by  the  blind  obedience  to  set  rules.  All 

photographer,  and  the  mere  tradesman,  to  whom  photography  is  simply  a  question  of  so 
much  a  day.  With  this  last  variety  we  have  nothing  to  do.  The  scientific  photographer, 
however,  is  a  very  respectable  person,  quite  ambitious,  and  often  of  high  attainments, 
but  entirely  mistaken  as  to  the  aims  of  photography  so  far  as  portraiture  is  concerned. 
The  great  object  of  the  scientific  photographer,  next  to  the  discovery  of  chemicals  which 
shall  be  more  reliable  and  more  rapid  in  their  action  than  those  hitherto  in  use  (an 
effort  in  which  he  is  seconded  to  the  fullest  extent  by  the  artistic  photographer),  is 
definition,  to  improve  his  lenses  his  greatest  care.  "  See  how  sharp  and  clear  this  picture 
is;  how  every  detail  is  made  out  into  its  minutest  particulars;  how  every  pore  of  the 
skin  shows  in  this  face ;  how  brilliantly  the  lights  and  shades  are  set  off  against  one 
another."  In  vain  will  the  artistic  photographer  plead  with  him  that  these  are  precisely 
the  qualities  least  wanted,  that  half  of  his  detail  ought  to  be  suppressed,  that  the  pores 
of  the  skin  ought  not  to  show,  that  these  brilliant  contrasts  of  light  and  shade  are 
destructive  of  harmony  and  tone ;  in  vain  will  he  endeavor  to  explain  the  merits  of  his 
own  work.  His  colleague  persists  that  it  is  blurred,  gray,  weak,  and,  therefore,  good  for 
nothing.  It  is  the  same  war  between  craft  and  art,  between  skill  and — pardon  the  pre- 
sumptuous word — genius,  which  has  lately  divided  the  ranks  of  our  wood-engravers. — 

S.  E.  KOEHLfcR. 

57.  Let  me  quote  from  an  essay  I  read  some  years  ago,  and  which  made  such  a  strong 
impression  upon  me  that  I  preserved  and  read  it  again  and  again,  and  which  will  eluci- 
date my  meaning  better  than  anything  I  can  say.  It  is  worthy  of  being  printed  in  letters 
of  gold,  and  hung  where  every  operator  in  the  land  must  see  it  daily  and  hourly : 

"  The  two  great  main  considerations  which  should  occupy  the  mind  of  every  photographer 
are  these :  What  is  the  best  view  he  can  take  of  his  sitter,  and  what  the  effect  of  light  and 
shade?  Which  will  be  most  becoming  to  that  sitter's  countenance  f  On  these  two  considera- 
tions the  success  of  the  portrait  entirely  depends." 

Now  as  to  the  question  of  view  there  is  some  tolerable  amount  of  understanding  mani- 
fested by  the  great  body  of  photographers.  The  sitter  is  generally  so  placed  that  the 
most  favorable  aspect  of  his  face  comes  before  the  lens,  and  so  that  the  rapid  perspective 
to  which  he  is  subjected  shall  distort  him  as  little  as  may  be. 

Such  rules  as  these  applying  equally  to  all  sitters  are  then  pretty  well  understood,  but 


150        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY 

laws  are  really  Nature's  laws,  and  all  things  affecting  us  as  beautiful  are  but  the 
varying  phases  of  Nature.  Art  itself  is  but  selections  from  nature,  and  even 
genius  is  only  the  preeminence  in  the  power  of  perceiving  what  is  beautiful  in 
nature,  else  how  would  men  who  are  not  geniuses  see  the  beauties  which  genius 
discovers  and  reveals  to  them.  Nature  is  inexhaustible  in  her  resources,  and 
the  revelations  she  manifests  to  great  minds  must  not  be  called  the  creations 
of  their  intellects.  The  superior  intellect  first  perceives,  but  others  less  gifted 
can  also  appreciate,  and  justly ;  it  is  therefore  no  excuse  to  say  that  we  live  in 
an  unpoetic  age,  or  in  a  period  unartistic.  Poetry  and  art  never  die.  And 
another  thing  is  true  :  The  photographer  lives  more  intimately  in  the  present, 

this  is  not  enough.  The  photographic  artist  who  would  wish  to  produce  a  really  suc- 
cessful portrait,  should  study  the  special  defects  and  special  beauties  of  the  individual 
before  him,  and  consider  in  what  view  the  faults  of  such  physiognomy  will  assert  them- 
selves least  strongly  and  the  merits  show  the  most. 

This  is  the  function  of  an  artist ;  of  a  man  of  considerable  natural  abilities  and  im- 
mense experience.  It  is  exercised  by  some  of  the  best  French  photographers  in  an 
eminent  degree. 

In  conclusion,  do  not  be  afraid  of  shadows,  proper  transparent  shadows  which  lie  in 
such  agreeable  masses  on  faces  which  come  in  the  range  of  our  skill.  I  do  not  mean 
those  fearful  innovations  that  have  lately  come  into  fashion,  fostered  by  those  who  ought 
to  know  better  than  to  take  every  one  in  a  style  misnamed  Rembrandt,  and  which  in 
most  cases  consists  of  patches  of  black  and  white  haphazardly  distributed  over  the 
human  face  divine,  and  when  analyzed  amounting  to  nothing  but  a  smudgy  dirty  thing ; 
but  lights  and  shadows  as  solid,  as  bright,  as  round,  and  as  finished,  as  when  the  sun 
flashes  brilliantly  and  warmly ;  which  are  as  different  as  such  sunshine  is  from  a  wet, 
dull,  cheerless,  monotonous  day.— DANIEL  BENDANN. 

I  remember  when  I  first  began  to  pay  attention  to  painting  I  used  chiefly  pure  colors, 
and  not  long  ago  I  was  reminded  of  my  former  method  by  hearing  an  artisi  say  that  the 
same  was  true  of  all  amateurs ;  hence  their  pictures  are  usually  crude ;  and  delicate  only 
after  they  have  had  experience.  They  subdue  their  colors  and  mix  them  with  white, 
making  them  more  neutral ;  the  result  of  it  is  that  when  you  examine  a  good  oil  painting 
or  a  water  color,  you  hardly  see  traces  of  the  pure  colors  of  the  palette.  The  tints  are 
almost  indescribable.  You  don't  know  exactly  how  they  are  made.  After  you  have 
had  experience  in  handling  these  colors  you  can  then  perhaps  solve  the  problem. 

I  remember  in  my  early  experience  looking  through  a  camera  at  a  sitter ;  I  could  not 
see  where  the  shadows  were  that  afterwards  developed  themselves  on  the  plate,  and  I 
have  no  doubt  that  many  young  photographers,  in  posing  their  subjects,  put  them  in 
certain  positions  because  they  know  a  good  effect  will  be  produced,  although  they  are  not 
able  to  see  in  the  camera  the  shadows  just  mentioned.  Now,  a  painter  learns  to  arrange 
lines  and  shadows  by  drawing  figures,  landscapes,  and  architecture ;  and  were  the.  pho- 
tographer to  draw  his  figures,  he  would  realize  the  necessity  of  a  good  arrangement  of 
light,  shade,  and  the  principal  lines.  As  photographers  you  can  scarcely  appreciate  that, 


THE    APPLICATION    OF    ART    PRINCIPLES.  151 

feels  more  its  full  force  and  value,  and  constructs  his  pictures  with  more  origi- 
nality from  the  material  at  his  hand,  than  the  painter,  though  the  camera  may 
be  a  more  humble  instrument  of  art  than  the  brush  and  palette.  When  some 
man  of  genius  shall  show  the  modern  world  the  beauties  which  its  heavy  eyes 
have  not  seen,  it  will,  on  looking  back,  be  conscious  of  the  fact  that  more  true 
originality  in  art  is  in  the  picture  by  the  artistic  photographer  than  in  the 
one  by  the  painter  of  the  nineteenth  century.  Necessity  has  compelled  him  to 
grasp  the  present,  and  art  to  extract  beauty  from  it.  Moreover,  the  more  he 
exercises  the  faculty  of  seeing  things,  the  more  individuality  will  there  appear 
in  his  productions. 

58.  And  this  brings  me  t* 
great  thing  in  art,  individual^ 
be,  let  it  show  his  own  study 

j»r,  according  to 
I  am  afraid.     I  know  that  in  ps 
stand  prominently  forward  as  the 
shadow  behind  it,  and  put  the  fijkvij, 
process.     Dore's  pictures,  if  you  e 

constructed,  so  far  as  light  and  shaue  is  cOficenretn — • ,.  „»•„.<_.,  .  ,JLJL  ±_ rf  _rr • 

to  photography  as  much  as  to  painting,  is  that  the  artist's  character  is  impressed  indelibly 
on  his  work.  If  he  is  a  refined,  intelligent,  and  cultivated  man,  you  will  see  it  in  his 
pictures.  If,  on  the  contrary,  he  is  gross,  boorish,  uncultivated,  you  will  see  that.  If  he 
is  an  awkward  man  you  will  see  the  same  in  his  pictures.  He  will  pose  his  subjects  as 
he  feels  himself,  and  according  to  his  understanding.  Notwithstanding  his  subjects  may 
be  awkward,  if  he  is  an  intelligent  and  a  refined  man,  if  he  has  a  high  idea,  it  will  still 
be  manifested  in  the  posing. — L.  W.  SEAVEY. 

But  there  is  yet  another  stage  of  progress  in  an  aesthetic  direction  to  be  mastered  by 
portrait  photographers.  We  want,  as  a  rule,  a  greater  variety  of  treatment,  more  regard 
for  individual  characteristics,  glass-room  arrangements  which  enable  us  to  experimentalize 
with  our  light  and  shade  on  living  models  as  readily  as  if  we  had  them  on  our  palette  or 
at  the  end  of  a  brush  or  pencil  before  the  painter's  canvas.  The  wonderful  gain  newly 
made  in  rapidity  of  exposure  should  enable  us  to  catch  transient  expressions  of  grace, 
beauty,  and  feeling,  instead  of  the  deadly  formal  stillness  and  fixed  rigidity  so  necessary 
in  the  old  long-exposure  days.  It  is  these  things  which  ennoble  the  art  of  portraiture, 
raise  it  to  a  loftier  standard  of  intellectual  culture,  and  give  it  degrees  of  worth  and 
value  to  which  in  their  absence  it  must  ever  remain  a  stranger.— A.  H.  WALL. 

58.  Individuality  I  should  term  the  expression  of  the  nature  of  the  artist  himself  in 
his  work.  The  strong,  as  a  student,  will  display  evidences  of  himself  in  his  work,  even 
though  the  same  work  contains  much  that  is  characteristic  of  his  master.  His  work  will 
not  so  literally  reproduce  that  which  his  master  places  before  him,  perhaps,  as  will  the 
work  of  a  man  of  less  talent  but  greater  imitative  ability.  For  that  reason,  persons  are 
apt  to  make  great  mistakes  in  estimating  the  relative  talents  of  art  students.  The  man 


152         WILSON'S  QUAKTEK  CENTURY  IN   PHOTOGRAPHY. 

a  value  far  above  that  of  the  most  exact  copy  or  imitation  of  the  work  of  any 
great  man. 

It  is  very  pleasant,  too,  for  one  who  is  familiar  with  art,  to  walk  into  an 
exhibition  gallery  and  be  able  to  pick  out  pictures  that  he  can  feel  acquainted 
with  without  the  introduction  given  by  a  catalogue,  though  he  may  never  have 
seen  them  before.  No  matter  in  what  form  a  man's  individuality  may  display 
itself,  when  you  have  once  learned  its  character  you  may  always  recognize  it, 
and  no  signature  is  necessary.  And  where  there  is  this  individuality,  you  may 
-,  lfi^  recognize  it  in  the  merest 

charcoal  sketch,  the  rough 
woodcut,  or  the  commonest 
reproduction.  You  cannot 
<ill  it,  however  feebly  you 
may  undertake  to  reproduce 
it.  No  one  who  has  enjoyed 
the  art  exhibitions  of  New 
iTork  will  fail  to  recognize 
lie  works  of  the  different 

great  painters  here,  without  the  help  of  either  initial,  name,  or  catalogue.  With 
none  is  this  more  truly  so  than  with  Mr.  F.  S.  Church,  whose  fine,  though 
weird  conceptions  possess  a  charming  individuality  which  cannot  be  mistaken. 
A  "Sketch"  by  this  great  painter  has  been  engraved  to  make  my  statement 
better  understood  (Fig.  166). 

who  draws  most  literally  is  not,  by  any  means,  necessarily  the  strongest  man  in  a  school, 
but  he  who  succeeds  in  appreciating  and  incorporating  the  spirit  of  wThat  he  attempts  to 
reproduce  into  his  work,  is  the  man  who  displays  the  most  evident  promise.  The  imi- 
tative faculty,  as  I  have  said,  is  an  important  element  in  the  artist,  but  one  that  is  of 
small  value  compared  to  the  creative  faculty.  '  A  monkey  is  a  close  imitator,  but  a 
monkey  does  not  invent  anything.  An  artist  must  be  able  to  imitate,  but  he  must  be 
able  to  do  a  great  deal  more,  and  as  he  does  more,  he  displays  the  individuality  that 
distinguishes  him  from  other  men,  and  we  enjoy  his  work  because  it  is  different  from 
that  of  other  men. 

Thackeray  and  Dickens  are  authors  whose  writings  we  enjoy,  because  they  are  so  true 
to  nature ;  but  beyond  that  there  is  a  great  charm  in  the  difference  of  the  styles  of  the 
two  men.  We  love  Dickens,  we  love  Thackeray,  and  yet  the  men  are  not  at  all  alike. 
And  it  is  not  so  much  what  they  tell  us  as  their  inimitable  way  of  telling  it  that  we 
delight  in  ;  not  so  much  the  books  as  the  men  themselves  displaying  their  characteristics 
to  us  through  their  books.  And  so,  in  art,  the  artist's  mind,  as  shown  through  his  work, 
is  much  more  fascinating  to  us  than  the  work  itself. — WILLIAM  HART. 


THE    APPLICATION    OF    ART    PRINCIPLES.  153 

59.  But  let  me  not  be  misunderstood.  Neither  the  faculty  of  seeing,  the 
exercise  of  taste,  nor  any  certain  individuality  in  your  work  can  be  attained 
without  thought  and  application.  For  not  until  these  are  practised  will  you 
feel,  and  without  feeling  you  cannot  be  a  true  artist.  Said  a  veteran  artist  who 
is  frequently  quoted  in  the  foot-notes : 

"  The  highest  art  is  felt,  rather  than  seen  or  heard.  It  is  the  echo  in  man 
from  the  voice  of  nature,  the  sympathetic  rapport  between  matter  and  spirit. 
Art  may  be  compared  to  a  lofty  pyramid  whose  broad  base  rests  on  the  ground, 
its  apex  being  lost  to  view  in  the  empyrean ;  between  its  gross  foundation  and 
its  iridescent  crown  steps  succeed  each  other,  tit  first  distinctly  separate,  but 
seeming  to  melt  into  each  other  above  like  those  upon  the  famous  tomb  of 
Cheops.  Truthful  representations  of  nature,  by  whatever  means  produced, 
belong  to  its  higher  degrees,  but  their  exact  place  cannot  well  be  determined, 
since  they  seem  higher  or  lower,  according  to  the  acuteness  or  dulness  of  the 
vision  of  the  beholder." 

59.  I  must  suppose  that  your  skylights  have  such  apparatus,  and  go  on  to  mention  a 
few  of  the  artistic  qualities  that  should  thereby  be  introduced. 

I  will  confine  myself  to  four,  the  four  chief;  all  of  them  should  coexist  in  every 
picture.  It  is  their  harmonious  union  which  creates  artistic  treatment,  redeeming  what 
would  else  be  vulgar  and  trivial.  In  a  measure  they  are  contradictory  and  opposing 
qualities,  but,  like  discords  in  music,  add  to  the  resulting  harmony. 

They  are  BREADTH,  DEPTH,  SOLIDITY,  TRANSPARENCY  ;  let  me  repeat  them,  breadth, 
depth,  solidity,  transparency.  I  ought  to  add  a  fifth,  delicacy,  but  that  will  appear  inci- 
dentally. 

Would  you  ask  me  for  a  formula,  in  what  proportions  to  mingle  our  four  qualities  ? 
That  cannot  be  given.  Here  it  is  that  subtle  thing,  taste,  has  its  play,  and  transcends 
rules.  This  offspring  of  a  chaste,  correct,  intelligent  feeling,  operating  through  a  trained 
eye,  must  be  your  supreme  court,  your  place  of  final  appeal. 

Endeavor  always  to  refine  and  balance  your  taste;  in  this  way  alone  can  the  eye  be 
brought  to  see  rightly,  for  the  eye  is  only  an  instrument,  and  does  only  what  the  mind 
sets  it  to  do,  and  with  only  the  amount  of  thoroughness  that  the  mind  desires ;  and  no 
mistake  is  commoner,  or  more  pernicious  to  art,  than  the  supposition  that  any  and  all 
eyes  can  see  the  whole  of  anything,  even  the  simplest  object.  No  eye  sees  the  whole; 
the  trained  eye  sees  best  and  most,  but  even  the  eye  of  your  camera  does  not  see  all,  and 
like  other  eyes  without  brains,  cannot  record  all  of  what  it  does  see. 

As  a  means  of  elevating  your  taste,  read ;  study  to  find  out  what  you  ought  to  admire. 
The  greatest  critic  of  modern  times,  Sainte-Beuve,  says  to  this  effect,  that  "in  looking 
at  any  work  of  art  we  ought  to  ask  ourselves,  not,  does  this  please  us,  but  ought  we  to  be 
pleased  with  this?"  To  this  end  read;  read  the  literature  of  your  profession. — W.  J. 
BAKER. 

The  utmost  capacity  of  photography  can  only  be  reached  when  with  complete  control 


154         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Just  as  a  learned  musician  may  spoil  all  effectiveness  by  lack  of  expression 
in  his  performances,  and  an  elocutionist  or  actor  fail  to  move  his  audiences  for 
want  of  the  ability  to  "  suit  the  action  to  the  word/'  so  may  the  artist  fail  to 
win  applause,  no  matter  how  strictly  he  follows  the  rules  of  composition  and 
chiaro-oscuro,  if  there  is  no  show  of  feeling  in  his  work. 

The  rightful  effect  of  all  kinds  of  study  should  be  to  exercise  and  excite  the 
imagination.  If  they  do,  then  there  is  growth.  In  art  the  effect  of  study 
of  the  works  of  others  is  to  make  us  more  observant.  Browning  has  said  that 
paintings  teach  us  to  notice  things  in  nature  that  never  would  have  been 
noticed  by  us  but  for  the  painting.  This  is  most  true.  Moreover,  when  we 
look  at  paintings  we  find  ourselves  comparing  the  work  of  the  artist  with  our 
own  knowledge  of  nature,  to  see  how  exactly  he  has  followed  nature.  This  is 
good  discipline,  and  causes  within  us  a  desire  not  only  to  follow  nature,  but  to 
exercise  our  imagination  in  bringing  out  from  nature  her  inmost  meaning. 

60.  All  the  impressions  made  upon  us  by  what  we  see,  exercise  what  is  called 

of  his  materials  the  operator  is  possessed  of  a  cultivated  mind,  master  of  the  principles 
which  govern  art,  and  deeply  imbued  with  its  spirit.  Mere  taste  is  not  sufficient ;  he 
must  have  thought,  too,  and  thought  is  the  result  of  culture.  Like  the  architect,  sculptor, 
or  painter,  he  ought  to  be  a  man  of  observation  and  able  to  segregate  the  essential  idea 
from  the  unnecessary  rubbish  which  surrounds  it.  Drawing,  modelling,  or  painting  are 
the  means  by  which  poetic  ideas  are  unfolded  in  plastic  art;  in  photography  the  chem- 
ical action  of  some  of  the  rays  of  light  upon  a  sensitized  film  or  medium  stands  for  two 
of  these,  and,  when  within  their  proper  sphere,  they  are  used  by  corresponding  intelli- 
gence, bear  corresponding  fruits.  Their  results  ought  to  be  preferred  to  thoughtless 
skill,  for  they  give  better  satisfaction. 

With  regard  to  the  claim  of  the  photographer  to  the  name  of  artist,  I  have  only  this 
to  say :  I  shall  always  be  as  ready  to  acknowledge  it  in  the  photographer  whe  possesses 
the  true  art-spirit  as  I  shall  be  unwilling  to  yield  it  to  the  painter  who  does  not.  The 
earnest  seeker  after  truth  does  not  stop  to  consider  by  what  name  he  is  called.  Words 
without  their  corresponding  sense  are  trifles  light  as  air.  No  fear  but  that  the  man  of 
genius  whose  words  prove  his  worth  will  be  known  and  recognized  as  artist,  while  no 
unsupported  claim  that  professional  pride  can  set  up  will  be  likely  to  be  treated  other 
than  with  the  contempt  it  deserves.  Without  love  and  self-sacrificing  devotion  to  art  a 
man  cannot  be  artist  in  the  only  sense  that  can  make  it  worth  the  aspiration. — L.  G. 
SELLSTEDT. 

60.  No  great  art  ever  was,  or  ever  can  be,  employed  in  the  careful  imitation  of  the  work 
of  man  as  its  principal  subject.  That  is  to  say,  art  will  not  bear  to  be  reduplicated.  A 
ship  is  a  noble  thing,  a  cathedral  is  a  noble  thing,  but  a  painted  ship  or  a  painted 
cathedral  is  not  a  noble  thing.  Art  which  reduplicates  art  is  necessarily  second  rate.  I 
know  no  principle  more  irrefragably  authoritative  than  that;  which  I  had  long  ago 


THE    APPLICATION    OF    ART    PRINCIPLES.  155 

in  art,  our  "  feeling."  No  one  who  understands  art,  can  be  devoid  of  feeling. 
He  enjoys  and  appreciates  what  he  sees  more  heartily  than  another,  and  his 
thoughts  are  fraught  with  tenderness  and  pathos.  He  cannot  close  Jiis  mind 
against  either  the  gladness  or  the  sorrow  of  his  fellow-men  ;  and  when  he  looks 
at  paintings  he  will  find  that  this  capacity,  this  gift  of  "  feeling,"  will  enable 
him  to  see  and  enjoy  more  than  those  who  are  not  blessed  with  it. 

Then,  when  you  have  so  imbibed  the  principles  of  art  as  to  love  them,  you 
will,  when  looking  at  pictures  or  communing  with  Nature,  feel  a  thrill — a 
degree  of  pleasure  which  those  who  have  no  aesthetic  sense  never  experience. 

As  the  fragrant  trailing  arbutus  reveals  its  hiding-places  most  quickly  to 
those  who  love  it  most,  so  do  Nature  and  pictures  unfold  their  charms  to  those 
who  love  them  in  a  way  which  the  uncultivated  are  not  privileged  to  understand. 

61.  We  do  not  need  to  go  further  for  an  illustration  of  "Feeling"  than  to 

occasion  to  express :  "  All  noble  art  is  the  expression  of  man's  delight  in  God's  work, 
not  his  own."  Mr.  Kuskin  must  be  understood  as  applying  to  the  newly  made  work  of 
man,  for  further  on  he  again  says  with  truth :  "  A  ruined  building  is  a  noble  subject, 
just  as  far  as  man's  work  has  therein  been  subdued  by  nature's."  And  further  on  still 
he  says :  "  A  wrecked  ship  or  shattered  boat  is  a  noble  subject,  while  a  ship  in  full  sail, 
or  a  perfect  boat,  is  an  ignoble  one ;  not  merely  because  the  one  is  by  reason  of  its  ruin 
more  picturesque  than  the  other,  but  because  it  is  a  nobler  art  in  man  to  meditate  upon 
fate  as  it  conquers  his  work,  than  upon  the  work  itself." — JOHN  KTJSKIN. 

61.  Art  knowledge  depends  upon  the  study  of  nature  in  its  aggregate  relations.  In  a 
good  picture  these  are  judiciously  preserved;  everything  is  in  keeping  and  harmony;  not 
any  one  object  or  part  is  absolutely  true  to  the  extent  of  deception,  for  if  it  were,  the 
others  could  not  be,  but  all  are  true  with  relation  to  each  other.  Such  a  representation 
of  nature  may  not  satisfy  the  mind  that  has  recorded  only  some  isolated  facts  and  is 
ignorant  of  others,  but  to  him  who  has  kept  his  eyes  open  to  God's  works  in  their  har- 
monious unity  it  will  be  a  revelation  of  their  author.  Said  a  recent  writer  on  art,  whose 
works  may  be  read  with  pleasure  and  profit:  " Nature  is  very  rich  and  art  is  very  poor; 
nature  has  a  million  to  spend  where  art  has  five  hundred.  What  is  the  most  precious 
thing  for  art  to  do?  There  are  two  ways  of  imitating  nature.  Art  may  spend  side  by 
side  with  nature,  degree  for  degree  of  light,  coin  for  coin  till  her  resources  are  exhausted, 
and  then  confess  herself  a  bankrupt.  Or  she  may  establish  a  scale  of  expenditures  suited 
to  her  resources ;  and,  abandoning  all  hope  of  rivalry  with  nature,  set  herself  to  the 
humble  task  of  interpreting  her.  And  here  is  the  first  essential  difference  between  pho- 
tography and  painting ;  a  difference  which  of  itself  is  sufficient  to  separate  them  forever. 
Poor  photography  spends  degree  for  degree  with  rich  nature,  and  is  of  course  very  soon 
exhausted,  but  poor  painting  husbands  her  resources  and  spends  a  penny  for  light  where 
nature  spends  a  pound."  I  may  remark  here  that  in  my  allusion  to  photographic  art  I 
refer  to  pure  photography,  at  least  as  the  impression  comes  from  the  retouched  and  per- 
fected negative.  In  the  case  of  pictures  finished  by  hand  in  India-ink,  colors,  or  char- 


15G 


WILSON'S-  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


FIG.  167. 


refer  again  to  "  The  Testy  Old  Squire's  Complaint."     But  we  shall  have  other 

examples,  which  I  have  selected 
from  my  store  of  such  things  for 
that  special  purpose. 

62.  The  first  is  "  First  Come, 
First  Served,"  by  Mr.  Frost 
Johnson — a  composition  not  be- 
yond the  ability  of  the  camera 
to  follow  very  closely.  The  law 
of  the  street  fountain  prevails 
here  as  is  well  declared  by  the 
figures,  and  yet  the  feeling  artist 
has  taken  care  so  to  provide  for 
the  horse  and  dog  that  they  may 
not  be  deprived  of  their  turn. 
Likewise  he  has  so  painted  the 
old  man  as  to  cause  you  to  wish 
you  could  make  way  for  him 
first,  and  bear  his  burden  for 
him  while  he  drinks. 

coal,  it  is  often  difficult  to  determine  to  whom  the  honor  or  disgrace  belongs,  whether  to 
the  operator  or  the  poor  artist  who  finds  his  bread  in  his  employ. — L.  G.  SELLSTEDT. 

62.  If  a  man  is  destitute  of  the  ability  to  create  anything,  it  is  his  misfortune ;  and  if 
he  experiences  pleasure  in  making  imitations  of  the  work  of  other  men,  there  can  be  no 
possible  objection  to  his  doing  it ;  only  we  should  not  dignify  his  performances  by  calling 
them  works  of  art ;  and  when  writers,  from  ignorance,  or  something  worse,  laud  such 
men  to  the  skies  as  great  artists,  it  is  no  wonder  that  the  papers  have  so  little  influence 
in  such  matters. 

No  great  artist  is  a  copyist,  and  no  man  of  real  power  will  hold  very  long  to  the  char- 
acteristics or  mannerisms  of  his  master.  Van  Dyck  was  a  pupil  of  Rubens,  but  he  did 
not  paint  like  him ;  Gerome  studied  under  Delaroche,  but  his  pictures  do  not,  in  the 
least,  resemble  those  of  his  master. — WILLIAM  HART. 

Now,  what  we  want  is  to  be  able  to  see  these  effects  of  a  face  fronting  the  light,  and  of 
excessive  top-light,  and  know,  at  a  glance,  how  to  remedy  them. 

As  I  have  already  said,  it  is  perhaps  only  necessary  that  attention  should  be  called  to 
this  matter  to  have  its  importance  understood  and  appreciated.  It  is  not  necessary  that 
you  should  wait  till  you  return  to  your  various  studios  before  you  begin  to  practise  a 
suggestion  of  this  kind,  but  it  may  be  commenced  here,  if  it  has  not  been  commenced 
before,  and  be  made  a  constant  study  everywhere  you  go.  A  careless,  uneducated 
observer  would  look  over  this  assembly,  from  the  seat  of  any  one  of  you  here,  and  notice 


THE    APPLICATION    OF    ART    PRINCIPLES. 


157 


63.  Again  have  we  a  study  of  "  Feeling "  in  Mr.  Samuel  Coleman's  "Sunny 
Afternoon  in  the  Port  of  Algiers."  If  ever  presented  to  you,  you  will  not  even 
focus  on  the  charming  line  of  dahabeehs  until  you  have  added  to  the  sense — 


Fio   1(58. 


the  feeling  of  repose — rest — by  placing  in  your  foreground  two  or  three  groups 
of  picturesque  Arab  sailors.  This  is  feeling — yielding  to  impression.  The 
very  element  which  causes  somebody  to  pay  $30,000  dollars  for  a  picture  of 

no  peculiarities  to  arrest  his  attention,  but  the  artist  photographer,  as  he  glances  around, 
takes  in  not  only  the  various  styles  of  features,  with  the  profiles,  three-quarters,  and  front 
views,  but  he  sees  every  variety  of  light  and  shade ;  he  sees  a  brother  photographer 
between  him  and  the  window,  illuminated  by  a  fine  Rembrandt  effect :  he  sees  another 
with  wonderful  relief  by  a  peculiar  effect  of  side-light.  Some  are  pleasing,  some  are 
repulsive;  some  he  admires,  others  he  condemns;  so  there  is  a  constant  study  and 
criticism  going  on  in  his  mind.  When  he  goes  home  and  goes  to  work  he  makes  no 
uncertain  moves ;  he  has  a  reason  for  everything  he  does,  and  his  work  testifies  that  his 
eyes  see  before  his  hands  execute. — E.  J.  CHUTE,  at  N.  P.  A.  Convention. 

63.  When  you  see  a  print  of  great  excellence,  or  a  peculiar  effect,  endeavor  to  find  out 
by  experiment  the  means  that  produced  it,  and  note  them.  Make  a  study  of  effects  in 
different  lights,  artificial  light,  the  light  of  a  room ;  when  any  of  these  seem  good,  try  for 
them  in  the  operating-room.  In  making  such  experiments  be  careful  that  you  obtain  as 
accurately  as  possible  the  effect  that  the  eye  sees.  There  will  always  be  a  great  diver- 
gence, but  be  sure  that  you  come  as  near  as  you  can. 

Do  not  let  yourself  be  a  mere  imitator  and  lose  your  own  individuality.  In  this  way 
you  are  in  danger  of  cultivating  faults,  for  if  you  start  out  to  make  pictures  like  so  and 
so's,  you  may  make  them  like  his  bad  ones  or  may  be  misled  by  a  reputation  above 
merit. 


158 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  169. 


two  swarthy  Arabs  kneeling  by  their  camels  in  the  desert,  in  answer  to  the 

Muezzin  call,  or  $10,000  for  an  old  drummer  and  fifer  tramping  along  a  dusty 

road  in  ?76.  Let  your  art  take  posses- 
sion of  you,  and  do  not  be  ashamed  to 
allow  the  fact  to  be  seen  in  your  work. 
64.  In  viewing  a-  picture  which  pre- 
tends to  be  any  sort  of  a  composition  our 
first  effort  should  be  to  interpret  and  un- 
derstand the  meaning  and  intention  of 
the  artist  in  producing  it.  And  then,' 
using  the  rules  given  us,  by  analysis, 
discover  whether  or  not  he  has  suc- 
ceeded in  carrying  out  his  object.  A 
good  picture  by  which  to  test  your 
ability  in  this  direction  is  Mr.  Wm. 
Magrath's  "  Girl  Spinning."  There  is 
a  close  following  of  nature  here,  in  ac- 
tion, in  accessory,  in  composition,  and  in 
the  light  and  shade.  All  are  in  har- 
mony and  make  a  real  picture.  There 
is  an  airy  cheerfulness  about  the  model, 

too,  which  indicates  that  she  is  a  maiden  of  that  dispensation  when  the  youth 

of  her  sex  were  expected  to  spin  their  own  bridal  outfits. 

Rather  seek  to  form  in  your  own  mind  a  type  of  beauty,  the  approximation  to  which 
will  stamp  all  your  work  with  the  seal  of  your  individual  purpose.  Be  true  to  yourself. 
Admit  no  half  work ;  make  it  your  first  object  to  please  yourself,  or  rather  to  gratify  your 
artistic  instincts,  and  the  pleasing  your  customers  a  secondary  consideration.  There  is 
always  a  conflict  between  taste  and  ignorance;  carry  it.on  as  courteously  as  you  may, 
but  yield  no  jot.  In  time  you  will  be  supported  by  those  who  really  can  discern,  whose 
opinion  is  received  by  many  who  do  not  judge  for  themselves. 

When  you  find  that  the  public  have  faith  in  you,  keep  faith  with  yourself  and  them  by 
doing  always  your  best. — \V.  J.  BAKER. 

64.  Now,  the  skill  of  the  artist  is  to  find  its  exercise  in  the  remedy  for  all  these  various 
conditions ;  and  his  taste  in  the  evocation  of  expression  will  be  called  into  great  and 
constant  demand.  The  subjects,  alas!  cannot  see  how  themselves  appear.  They  think 
they  are  doing  the  fine  thing,  just  when  they  are  making  themselves  appear  most  ridicu- 
lous. The  operator  must  manage  them  to  his  own  taste,  and  must  do  it  without  offending 
their  vanity,  or  treading  upon  their  peculiarities,  of  which  we  all  have  a  good  share. 
How  to  do  all  this  is  of  course  a  problem,  and  one  as  diversified  as  the  persons  who 


THE    APPLICATION    OF    ART    PRINCIPLES 


150 


65.  The  sentiment  or  conception  of  a  picture,  however,  does  not  yield  the 
only  opportunity  for  the  artist  to  display  feeling.  As  was  indicated  in  the 
very  beginning  of  this  chapter,  -pIG 

everything  may  be  ruined,  all 
picturesqueness  destroyed,  by  the 
careless  or  ignorant,  management 
of  the  light.  Therefore  the  ar- 
rangement of  the  light  and  shade 
in  a  picture  offers  the  artist  a  good 
opportunity  for  the  display  of 
feeling.  What  better  example  of 
this  do  we  need  than  the  lovely 
composition  of  Jennie  Browns- 
combe — "We  all  do  fade  as  a 
leaf?"  The  faded  leaf  is  the 
subject  of  consideration.  All  eyes 
are  directed  to  it ;  and  the  prin- 
cipal lights  are  upon  the  faces  so 
directed  as  to  give  full  value  to 
the  sentiment  of  the  composition. 
How  deftly  too  are  the  shadows 
managed — each  mass  caused  to  bring  out  the  value  of  some  corresponding 

present  themselves  before  him.  He  has  to  render  into  respectable  appearance  all  the 
variety  of  human  character  itself,  and  he  cannot  be  expected  to  succeed  in  this  without 
careful  and  perpetual  reflection.  Every  sitter  is,  therefore,  a  new  and  independent  study. 

The  mouth  is  easily  arranged  into  respectable  expression.  The  nasal  organ  expresses 
itself  in  spite  of  everything ;  and  so  does  the  cheek.  The  brow  is  dependent  upon  the 
eye,  and  the  eye  is  the  most  refractory  and  defiant  of  all.  When  one  sits  down  to  look 
quietly  at  nothing,  the  expression  of  the  eye  naturally  subsides  into  blank  vacancy. 
There  is  a  sort  of  excitement  in  sitting  for  a  picture  like  that  of  having  a  tooth  drawn, 
though  without  the  dread  of  pain.  The  heart  is  generally  making  better  time  than 
usual ;  and  the  eye,  sympathizing,  will  often  remain  entirely  expressionless,  or  will  for- 
tify itself  with  a  frown.  This  condition  of  affairs  is  aggravated  by  the  necessity  of  a 
bright  light  from  above,  which  taxes  its  strength,  and  by  the  fixed  gaze  maintained  for 
several  moments  upon  one  point,  not  generally  very  distinct.  The  result  is  apt  to  be  a 
poor  picture,  because  the  eyes  are  unnatural  and  meaningless. — REV.  A.  A.  E.  TAYLOR. 

65.  I  have  lately  been  examining  some  of  the  best  plain  photographic  portraits  I  can 
find,  and  they  seem  to  me  to  be,  as  the  artist  says,  "  out  of  keeping."  At  first  sight  they 
appear  perfect,  and  all  right,  but  they  don't  wear  well.  After  a  little  study  they  grow 


160         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

mass  or  twinkle  of  light.  So  much  for  an  outdoor  study,  not  too  difficult  for 
the  camera  to  equal  in  every  respect. 

weak,  and,  unlike  good  art,  they  do  not  reveal  some  fresh  beauty  every  day.  The  like- 
ness is  there,  but  it  is  thin  and  spectral — the  inner  light  fades  out  of  them,  and  in  a  little 
while  they  are  lifeless  and  automatic.  Looking  carefully  for  the  cause  of  this,  I  think  it 
is  found  in  the  lack  of  artistic  cultivation  in  the  photographer.  Of  course,  I  am  not  com- 
petent to  say  how  much  of  it  is  due  to  the  imperfections  of  machines  and  materials,  but 
the  difference  between  an  artistic  photograph  and  a  bad  one  is  already  so  great  that  I 
believe  much  more  may  be  accomplished  with  the  material  now  in  use.  Whatever  im- 
provement may  be  made  in  the  means,  I  still  think  true  progress  is  to  be  gained  by  the 
study  of  photography  as  a  fine  art,  using  exactly  the  same  methods  employed  by  the 
great  artists  of  all  time.  Often  a  work  of  art  is  easier  to  study  than  nature.  One  needs 
sometimes  a  teacher,  and  the  best  pictures  are  the  best  masters.  If  every  photographic 
artist  could  have  one  of  Titian's  portraits  hanging  in  his  studio,  the  result  would  soon 
be  seen  in  our  likenesses.  In  these  portraits  there  are  no  dead  surfaces,  there  is  no  dis- 
tortion ;  the  soul  looks  forth  from  its  windows  with  a  lofty  tranquility. 

In  these  likenesses  there  is  no  striving  for  any  transitory  effect.  No  part  of  the  face 
or  head  is  put  in  deep  shadow,  all  is  clear  and  sunny.  There  is  no  flinching  from  hard 
work.  Wherever  shadow  is  used,  the  modelling  is  continued  perfectly  throughout  the 
whole.  In  the  best  faces  of  Titian  no  shadow  is  apparent,  yet  there  is  no  flatness ;  they 
are  full  and  round,  like  nature  herself.  And  some  of  the  best  heads  of  Kembrandt,  fond 
as  he  was  of  shadow  tricks,  are  painted  in  this  broad  and  sunny  way.  These  great  artists 
studied  to  give  the  sum  of  human  life — not  five  minutes  of  it.  We  feel  in  the  presence 
of  one  of  their  portraits  that  we  have  the  whole  individual  before  us,  his  achievements 
and  his  possibilities.  They  are  as  beautiful  as  infancy  and  as  immutable  as  death. — A 
Sculptor. 

Long  experience  will  show  that  the  two  sides  of  every  face  differ.  This  is  very  evi- 
dent in  many  faces,  and  in  all,  however  regular  the  eyes  may  seem,  or  however  straight 
the  nose  may  appear,  close  observation  will  discover  that  one  side  is  better  than  the 
other.  It  is  this  side  that  should  be  taken. 

In  photographic  portraiture  the  face  should,  as  a  general  rule,  be  turned  away  from 
the  light.  If  the  face  is  turned  to  the  light,  however  delicate  the  half-tones  may  be,  the 
line  of  the  nose  will  be  partly  lost  in  equal  light  on  the  cheek  behind  it.  The  only 
exception  to  this  rule,  that  the  face  should  be  turned  from  the  light,  is  in  the  case  of  a 
profile,  or  the  profile  showing  a  glimpse  of  the  off  eye  when  the  nose  comes  clear  against 
the  background.  For  these  reasons,  that  is,  because  it  is  necessary  to  choose  which  side 
of  the  face  is  to  be  represented,  and  because  the  face  must  be  turned  from  the  light,  it  is 
well  to  have  a  studio  so  constructed  that  the  light  can  be  obtained  from  the  right  or  the 
left.  It  is  also  well  to  have  it  sufficiently  wide  to  enable  the  operator  to  work  diagonally, 
and  thus  get  a  modification  of  the  shadows  without  the  use  of  reflectors. 

As  regards  the  position  of  the  head,  Burnet  observes:  "Every  one  who  takes  the 
trouble  to  reflect  must  perceive  that  all  faces  contain  two  points  of  view,  where  the  char- 
acter is  more  or  less  developed — a  profile,  and  what  is  termed  a  front  view ;  and  that  the 


THE    APPLICATION    OF    AKT    PRINCIPLES.  161 

66.  An  interior  illustration  of  the  same  import  may  be  found  in  "  The  Sabot 
Maker"  (Fig.  171),  by  Mr.  E.  M.  Ward.      This  shows  how  a  strong  light 

seat  of  a  strong  likeness  lies  sometimes  in  one  greater  than  the  other.  They  must  also 
perceive  that  what  is  called  a  three-quarter  view  of  the  head  gives  the  artist  an  opportu- 
nity of  representing  both."  A  full  face  is  seldom  so  agreeable  in  photography  as  one 
slightly  turned  away. — JOHN  L.  GIHON. 

66.  There  are  a  few  fundamental  rules  which  regulate  the  harmonious  disposition  of 
pictorial  light  and  shade,  and  from  which  no  successful  departure  is  possible.  These 
are  so  absolute  and  apparent  that  I  may  state  them  as  axioms. 

Axiom  1.  The  general  scheme  of  light  and  shade  must  be  simple. 

Axiom  2.  The  point  (or  region)  of  greatest  interest  shall  be  the  point  (or  region)  of 
greatest  intensity,  or  of  contrast. 

Axiom  3.  All  other  contrasts  must  not  only  be  subordinate  to  this,  but  shall  tend  to 
give  it  value  or  prominence. 

Axiom  4  The  transition  from  light  to  shade,  and  vice  versa,  shall  be  gradual. — HUGH 
BREBNER. 

Shadows  are  natural  attendants  of  light,  and  the  student  of  nature  will  observe  how 
one  always  balances  tjie  other.  This  is  in  accordance  with  the  law  of  compensation  that 
follows  in  everything  throughout  the  universe,  and  it  is  only  by  a  careful  study  of  nature 
that  we  learn  to  distinguish  the  causes  that  influence  us  in  viewing  a  scene,  to  pronounce 
it  grand  or  insipid. 

In  reproducing  what  we  see  in  nature  by  what  is  termed  art,  extensive  shades  con- 
tribute greatly  to  the  beautiful  as  well  as  the  grand  and  majestic  result  of  the  whole 
together ;  they  equally  serve  to  give  richness  and  grace  to  the  middle  tints,  and  brilliancy, 
beauty,  and  animation  to  the  masses  of  light ;  they  also  afford  a  repose  no  less  grateful 
and  necessary  to  prevent  the  fatigue  and  overexertion  of  the  sight  on  the  illuminated 
parts.  To  this  end,  all  the  obscure  or  dark  parts  should  be  so  arranged  as  to  form  one 
general  mass,  and  its  greatest  force  collected  into  some  one  part,  where  it  will  have  the 
best  effect,  and  become  a  principle  on  which  all  the  others  are  in  a  graduated  and 
harmonious  dependence. 

The  photographic  art  student  will  readily  understand  the  application  of  these  sugges- 
tions to  his  daily  practice.  Whether  it  be  a  head,  a  three-quarter  length,  or  a  full  figure, 
the  application  remains  the  same.  The  test  of  skill,  however,  is  with  the  first  of  these, 
for  it  is  only  in  that  perfect  blending  of  shadow  with  light,  rounding  up  to  the  highest 
part  where  the  pure  light  is  but  a  mere  point,  and  falling  off  through  the  delicate  grada- 
tions of  tints  into  the  deepest  shadow,  that  a  head  can  claim  to  be  artistic  in  composition 
of  light  and  shade. 

It  is  gratifying  that  the  days  of  white  pictures  have  passed,  and  it  has  been  demon- 
strated that  extensive  shades  are  admissible  in  a  portrait,  as  well  as  in  a  landscape  where 
rocks  and  hills  cast  their  grim  shadows  and  give  grandeur  to  the  scene ;  that  a  face  may 
receive  the  same  treatment  at  the  hands  of  an  artist  that  nature  accords  to  her  works 
everywhere,  and  be  more  truthful,  more  pleasing,  more  life-like.  The  shadows  and 
middle  tints  give  support  and  brilliancy  to  the  lights ;  there  is  no  glare ;  the  eye  does 

11 


162 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  171. 


may  be  employed  without  transcending  the  laws  of  taste;  and  in  this  case 
the  lighting  is  a  large  part  of  the  charm  of  the  picture,  because  the  interior 

of  the  workshop  is  dark,  and  the 
light  is  only  directed  where  it  is 
wanted — upon  the  subject. 

When  we  go  further  into  the 
subject  of  light  and  shade,  this 
capital  picture  may  serve  us  a  good 
purpose  again. 

Those  who  are  always  looking 
for  quaint  subjects  among  the 
good  people  of  our  rural  districts 
will  find  more  than  one  fine  sug- 
gestion in  "  The  Sabot  Maker." 

67.  Not  only  the  masters  in  art 
but  their  works,  tell  us  that  the 
management  of  light  and  shade  in 
a  composition  requires  great  care 
and  study.  The  adaptation  of 
it  to  the  character  of  the  subject 
is  not  only  to  be  considered,  but 
the  quality  of  draperies,  acces- 

not  tire  but  wanders  from  point  to  point  continually  attracted  by  the  sense  of  complete- 
ness and  repose  that  characterizes  the  whole.  An  important  consideration  in  a  bust 
portrait  is  to  give  it  a  well-shaded  background,  the  deepest  parts  against  the  lights  in 
the  model ;  this  is  indispensable  to  the  brilliancy  and  beauty  of  the  face. — EDWARD  L. 
WILSON. 

67.  The  photograph  is  to  so  great  an  extent  Nature's  work  that  we  must  always  see 
her  individually  stamped  upon  it,  and  read  in  it  to  a  greater  or  less  extent  those  details 
of  character  which  give  such  interest  to  pictures. 

Beginning  with  one  figure,  one  of  the  simplest  subjects  that  we  can  have,  to  make  a 
picture,  for  a  human  figure  with  its  component  parts  of  interest,  if  at  all  picturesquely 
clothed,  may  make  a  complete  picture,  we  have  at  once  an  opportunity  to  show  taste 
and  skill  in  so  disposing  the  head  and  limbs  that  by  reversing  the  lines  of  action  and 
varying  the  curves  and  angles,  we  get  grace  and  dignity  instead  of  stiffness  and  vulgarity. 
Then,  suppose  we  begin  to  introduce  some  surrounding  objects  to  give  subject  for  thought 
and  increased  interest;  we  choose  those  that  will  be  in  harmony  with  the  subject  of  our 
work.  About  an  intellectual  man  we  introduce  features  familiar  in  a  library,  we  would 
surround  a  hunter  with  implements  of  the  chase,  a  traveller  or  seafaring  man  should 


THE    APPLICATION    OF    ART    PRINCIPLES.  163 

series,  etc.,  in  regard  to  their  power  of  absorbing  or  reflecting  light;  the 
mechanical  arrangement  of  light  and  shade  that  will  be  produced,  and  the  force 
and  nature  of  colors  that  may  affect  the  composition. 

68.  Whether  the  picture  be  a  group  or  have  but  one  principal  figure,  the 
arrangement  of  light  should  be  such  as  to  give  prominence  to  the  principal 
subject,  by  avoiding  the  introduction  of  anything  that  will  draw  the  attention 

have  objects  indicative  of  those  callings,  and  our  next  aim  would  be  to  dispose  these 
accessories  in  such  a  manner  that,  while  they  added  to  the  fulness  and  interest  of  the 
picture,  they  would  be  in  entire  subservience  to  our  main  feature.  This  simple  begin- 
ning of  telling  a  story  should  be  led  on  and  built  upon  as  we  proceed;  for,  although  a 
work  may  be  complete  and  beautiful  simply  as  a  work  of  art  and  without  telling  a  story, 
how  infinitely  wider  will  its  range  of  interest  be  if  it  does  tell  a  story,  and  this  additional 
interest  need  never  detract  from  it  as  a  work  of  art.  If  we  were  advancing  further  and 
introducing  two  figures  in  our  picture,  we  surely  would  not  have  them  sitting  bolt  upright 
and  staring  at  us,  but  by  so  posing  them  as  to  express  the  conveying  between  them  of 
some  sentiment  or  emotion,  or  by  the  introduction  of  some  object  of  interest  common  to 
them  uniting  them,  we  would  have  at  once  made  an  advance  toward  a  picture;  and  so 
we  go  on  introducing  more  figures  and  «iore  objects  necessary  to  give  point  and  fulness 
to  our  tale.  But  then  our  difficulties  increase,  for  in  proportion  as  we  gain  intricacy, 
variety,  and  interest,  we  are  apt  to  lose  that  simplicity  which  makes  a  work  striking  and 
impressive ;  our  various  objects  begin  to  scatter  the  attention  and  divert  it  from  the  main 
feature  or  point  of  our  story.  So  we  must  ever  keep  it  foremost  in  our  minds  that,  if  it 
be  possible  to  do  so,  we  must  have  a  main  central  feature  or  group,  with  other  features 
or  objects  taking  second,  third,  and  fourth  places,  the  interest  dying  out  as  we  approach 
the  edges  of  our  picture. — XANTHUS  SMITH. 

We  now  come  to  the  subject  of  composition.  So  far  as  we  have  gone,  we  have  learned 
that  what  language  is  to  the  poet  so  are  form,  light  and  shade,  color  and  accessories,  to 
the  artist.  When  we  have  mastered  these  elements,  we  are  ready  to  compose  according 
to  the  requirements  of  our  art.  Nature  steps  in  too,  now,  insisting  upon  obedience  to 
her  laws,  with  which  one  must  be  well  acquainted,  before  he  can  proceed  far  in  the  art 
of  composition. 

Fortunately  our  work  is  made  easier,  from  the  fact  that  we  are  not  called  upon  to 
make  pictures  continually  of  actors  wherein  we  must  represent  tragedy  or  comedy,  but 
what  we  do  have  to  (Jo  is  to  make  our  productions  lifelike,  i.  e.,  like  the  living,  natural 
persons  before  our  cameras,  and  we  must  see  that  our  poses,  lighting,  etc.,  harmonize 
with  the  character  of  the  subject  in  hand.  We  should  never  lose  sight  of  this  law  of 
unity,  for  on  it,  more  than  on  any  other,  depends  the  pleasing  effect  of  our  work. — M.  L. 
DWIGHT. 

68.  It  depends  as  much  upon  inspiration  as  any  human  work.  We  do  not  know  how 
or  why  an  idea  comes  to  us,  and  I  doubt  if  any  artist  who  has  hib  upon  a  happy  arrange- 
ment of  his  theme  can  state  how  he  found  it.  Certain  elementary  notions  there  are,  as 
that  there  must  be  a  leading  idea  to  which  all  the  facts  of  the  picture  tend — a  leading 


164        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

away  from  the  central  figure  or  figures.  If  a  group  is  to  be  photographed, 
such  an  arrangement  of  light  must  be  made  as  will  illuminate  the  whole,  and 
give  prominence  to  the  figures  composing  the  group,  rather  than  to  background 
or  accessories.  As  to  the  nature  of  materials  that  compose  a  group,  violent 
contrasts,  such  as  black  and  white  drapery,  should  be  avoided.  The  light 
cannot  be  arranged  to  do  justice  to  such  extremes,  and  the  harmony  of  the 
lighting,  as  well  as  the  composition,  is  often  destroyed. 

With  a  single  figure,  the  whole  arrangement  is  more  under  the  control  of  the 
artist  than  with  a  group,  and  the  various  points  of  the  picture  can  be  studied 
to  produce  the  best  possible  effect.  The  nature  of  the  light  best  adapted  for 
the  subject  is  the  first  consideration.  If  light  drapery,  a  much  more  subdued 
light  will  be  required  than  for  dark,  and  the  accessories  must  be  arranged  so  as 
not  to  be  entirely  lost  by  contrast.  The  observation  in  reference  to  extremes 
of  black  and  white  applies  here  as  well  as  in  groups,  and  with  white  drapery, 
anything  that  absorbs  light  to  any  great  degree  should  be  avoided. 

69.  The  source  and  direction  of  the  light  must  be  considered  according  to  the 

light  to  which  other  lights  are  subordinate.  But,  after  all,  the  composition  must  depend 
upon  the  artist's  individual  feeling. 

There  can  be  no  doubt  that  this  feeling,  this  sense  of  fitness  and  harmony,  may  be 
cultivated.  It  may  be  developed  by  familiarity  with  the  works  of  artists  who  possessed 
it  conspicuously.  There  are  some  artists  who  in  their  best  days  could  not  make  a  mis- 
take. You  will  find  false  composition  in  their  work  as  rare  as  discords  in  Mozart.  Any 
work  of  a  good  period  of  Greek  art  will  also  be  found  faultless  in  this  respect.  The 
Laocoon  is  not  of  the  best  period,  but  it  would  puzzle  a  convention  of  modern  artists  to 
rearrange  it.  The  infinitely  subtle  nature  of  the  art  of  composition  is  shown  by  the 
failures  made  in  restoring  mutilated  statues— as,  for  instance,  the  utter  impossibility  of 
replacing  the  lost  arms  of  the  Venus  of  Milo. 

This  art  of  composition  is  a  part  of  photography,  just  as  it  is  of  music  or  architecture, 
or  of  any  other  of  the  fine  arts.  It  enters  into  the  construction  of  the  simplest  picture. 
One  view  of  a  face,  unless  it  is  well  chosen,  is  often  of  little  value  as  a  likeness.  Suppose 
we  catch  a  swift  glimpse  of  a  stranger's  profile;  it  is  very  little  we  know  of  his  face  and 
character  until  we  have  seen  more  of  him.  But  a  momentary  glimpse — one  look  of  the 
face—  is  all  that  a  photograph  likeness  gives  us.  The  moment  you  begin  to  arrange  your 
sitter  to  get  the  most  of  him  before  the  camera,  you  are  studying  the  art  of  composition. 
Every  change  of  position,  every  object  you  introduce,  every  .bit  of  light  and  shade  aug- 
ments or  diminishes  the  value  of  the  picture. — L.  G.  SELLSTEDT. 

69.  First  of  all  screen  off  the  direct  top-light.  The  face  is  still  flat,  but  the  many 
downward  shadows  have  disappeared.  Now  screen  off  one  side  as  well  as  the  top-light, 
and  the  face  is  not  like  the  same.  With  the  light  all  round  the  face  it  would  appear 
broad,  flat,  and  altogether  deficient  in  character.  Now  it  is  just  the  reverse ;  there  is  too 


THE    APPLICATION    OF    ART    PRINCIPLES.  165 

nature  of  the  composition.  According  to  the  rules  of  art,  a  top  light  produces 
the  best  effect,  by  allowing  every  part  of  the  picture  to  be  more  clearly  denned. 
An  oblique  or  side  light  casts  the  shadow  of  one  object  upon  another,  and 
sometimes  runs  them  together  in  confusion.  In  portraiture,  however,  care 
must  be  taken  with- a  top  light,  to  avoid  heavy  shadows  on  the  face.  In  land- 
scape photography,  where  the  principal  points  are  much  separated,  an  oblique 
light  is  very  effective  in  giving  force  and  expression  to  the  composition. 

Unity  of  light  in  a  picture  is  an  established  rule  of  art,  founded  on  a  law  of 
nature.  This  rule  is  not  so  applicable  to  groups  for  portraiture,  where  we  are 
obliged  to  light  all  equally  well,  as  far  as  possible,  as  it  is  to  the  style  of 
grouping  known  as  genre  composition.  But  in  pictures  of  the  latter  class,  as 
well  as  those  of  single  portraiture,  the  principal  figure  should  be  placed  in  the 
focus  of  light,  while  everything  else  is  subordinate.  The  centre  figure  then 
becomes  the  centre  of  observation ;  for  the  eye  is  ever  attracted  by  light,  and 
turns  instinctively  to  it.  Gradation,  so  indispensable  to  harmony,  requires  the 

much  light  on  one  side  and  too  much  shadow  on  the  other ;  every  prominence  upon  the 
face  is  exaggerated,  and  the  texture  of  the  skin  shows  with  a  coarseness  which  is  far  from 
natural.  As  Artemus  Ward  says,  "Why  is  this  thus?"  Because  there  is  too  much 
direct  side-light.  Screen  off  the  side-light  until  you  get  a  delicate  shadow  upon  the  edge 
of  the  lighted  side  of  the  face.  This  will  send  the  ear  and  the  retiring  edge  of  the  cheek 
into  their  proper  places,  and  concentrate  the  highest  lights  where  they  should  be — upon 
the  forehead,  over  the  eye,  upon  the  nose  and  chin;  but  still  the  shaded  side  of  the  face 
is  too  dark  for  photographing.  And  here  come  the  differences  in  practice.  Some  would 
use  a  screen  to  soften  the  shadow  and  give  reflected  lights.  This  is  right  enough  if  you 
use  large  screens  and  keep  them  far  enough  away  from  the  sitter  to  give  the  reflected 
lights  as  they  would  be  if  reflected  from  the  side  of  a  room.  In  my  own  practice  I  prefer 
to  use  a  little  of  my  far-off  top-light  to  soften  the  shaded  side,  but  then  my  studio  is  very 
small,  and  I  get  my  reflections  from  the  wall  of  the  studio ;  in  a  wider  place  reflecting 
screens  would  be  necessary. 

There  is  nothing,  I  think,  so  useful  as  a  three-leaved  screen  hinged  and  upon  castors, 
white  on  one  side  and  gray  upon  the  other,  and  so  hinged  that  one  leaf  of  each  color  can 
be  brought  into  the  other  if  wanted.  The  facility  with  which  the  leaves  can  be  placed 
at  any  angle  for  reflection  is  of  great  value.  Small  hand-screens,  are,  in  my  opinion,  a 
mistake.  They  concentrate  reflected  lights  upon  the  face  only,  and  sometimes  only  on 
parts  of  the  face.  The  screen  should  be  large  enough  to  give  the  same  reflected  lights  upon 
both  face  and  drapery. 

So  far,  then,  in  making  a  portrait.  What  comes  next  to  make  it  a  picture  ?  A  photo- 
graph may  be  a  likeness,  and  yet  not  be  either  a  picture  or  a  faithful  portrait.  To  make 
a  picture  it  should  have  expression,  repose,  concentration,  and  keeping. — GEO.  HANMER 
CKOUGHTON. 


166         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

same  attention  in  lighting  the  different  figures  of  a  composition,  so  that  a  perfect 
blending,  from  the  principal  figure  in  the  strongest  light,  to  that  of  the  least 
importance,  in  the  deepest  shadow,  may  be  secured  as  in  lighting  a  single  face, 
where  a  harmonious  gradation  from  the  highest  light  to  the  deepest  shadow  is 
now  so  universally  sought  for  and  obtained.  It  will  be  readily  seen  that,  under 
the  proper  regulation  of  laws,  light  is  to  the  artist  a  language  or  medium  of 
expression,  the  due  observance  of  which  enables  him  to  make  clear  the  plan  of 
his  picture,  and  give  the  interpretation  he  desires. 

70.  Objects  receiving  light  should  not  be  extended  to  the  margin,  because, 

70.  There  is  no  better  test  than  your  having  made  the  white  in  your  picture  precious, 
and  the  black  conspicuous.  I  say,  first,  the  white  precious.  I  do  not  mean  merely  glit- 
tering or  brilliant ;  it  is  easy  to  scratch  white  sea-gulls  out  of  black  clouds,  and  dot 
clumsy  foliage  with  chalky  dew ;  but  the  white  when  well  managed  ought  to  be  strangely 
delicious,  tender  as  well  as  bright,  like  inlaid  mother-of-pearl,  or  white  roses  washed  in 
milk.  The  eye  ought  to  seek  it  for  rest,  brilliant  though  it  may  be ;  and  to  feel  it  as  a 
space  of  strange  heavenly  paleness,  in  the  midst  of  the  flashing  of  the  colors.  This  effect 
you  can  only  reach  by  general  depth  of  middle  tint,  by  absolutely  refusing  to  allow  any 
white  to  exist  except  where  you  need  it,  and  by  keeping  the  white  itself  subdued  with 
gray,  except  at  a  few  points  of  chief  lustre. 

Secondly,  you  must  make  the  black  conspicuous.  However  small  a  point  of  black 
may  be  it  ought  to  catch  the  eye,  otherwise  your  work  is  too  heavy  in  the  shadow.  All 
the  ordinary  shadows  should  be  of  some  tint — never  black,  nor  approaching  black.  They 
should  be  evidently  of  a  luminous  nature,  and  the  black  should  look  strange  among 
them;  never  occurring  except  in  a  black  object,  or  in  small  points  indicative  of  intense 
shade,  in  the  very  centre  of  masses  of  shadow. — JOHN  RTJSKIN. 

Pictures  that  are  composed  nearly  or  entirely  of  half  light  or  half  shadow  are  always 
tame.  And  when  high  light  predominates,  there  is  a  flimsiness  and  weakness  which 
cannot  attract  or  produce  a  fine  impression.  And  again,  where  all  is  in  shadow,  there  is 
a  sombreness  which  is  only  suited  to  certain  gloomy  scenes  where  all  is  wrapt  in  dark- 
ness and  mystery.  It  should  be  the  aim  of  the  artist,  therefore,  in  those  subjects  where 
he  has  to  deal  with  high  light  over  nearly  his  entire  picture,  to  introduce  a  few  well 
arranged  spots  of  dark,  seeing,  however,  always  that  they  be  not  equal  in  importance. 
Some  of  the  Flemish  painters,  during  the  best  period  of  their  art,  made  beautiful  pictures 
of  open  daylight  scenes  on  the  coast  and  in  their  flat  country,  by  the  introduction  of  a 
few  well  disposed  figures,  or  a  group  of  picturesque  boats,  which,  as  distinct  points  of 
deep  shadow,  gave  sufficient  force  to  what  would  otherwise  have  been  utterly  valueless 
works  on  account  of  the  monotonous  light  of  the  gray  sky  and  sea  or  marshy  country. 

In  pictures  where  half  shadow  and  deep  shadow  predominate  over  the  whole  subject, 
the  introduction  of  a  spot  of  high  light  with  a  little  supporting  half  light,  will  so  set  at 
naught  the  monotony  as  to  make  most  interesting  and  powerful  works.  The  high  light 
though  should  be  of  an  agreeable  form,  especially  in  that  portion  where  it  comes  in 
greatest  relief  against  the  dark. 


THE    APPLICATION    OF    ART    PRINCIPLES. 


167 


in  the  first  place,  the  lights  cannot  be  well  supported  by  the  shades ;  in  the 
next,  extending  the  lights  quite  to  the  boundary  gives  the  effect  of  an  unfinished 
picture,  which  destroys  the  unity  so  essential  to  the  harmony  and  completeness 
of  the  subject. 

The  most  agreeable  pictures  are  generally  those  in  which  half  light  or  half  shadow 
predominates,  with  a  small  portion  of  very  deep  shadow  and  brilliant  high  light ;  and  per- 
haps the  most  complete  arrangement  of  light  and  dark  is  that  in  which  the  work  is  divided 
into  about  one-half  of  half  light  and  one-half  of  half  shadow,  with  a  sum  total  of  high 
lights  amounting  to  one-eighth  of  the  surface  of  the  work  and  as  much  deep  shadow.  This 
to  many,  at  the  present  time,  I  know,  will  seem  like  conventional  stuff;  but,  if  any  one  of 
good  taste  will  look  over  a  lot  of  photographs  of  either  landscapes  or  interiors  or  figure 
pieces,  and  lay  aside  those  which  strike  him  as  being  agreeable  pictures,  and  then  note  the 
proportions  of  light  and  dark  which  they  contain,  I  think  he  will  find  that  they  conform 
more  or  less  to  the  above.  I  will  give  an  example.  (Fig.  172. )  It  is  a  view  on  the  western 
coast  of  the  Island  of  Heligoland,  by  Hermann  Eschke.  The  work  is  composed  largely 

FIG.  172. 


of  half  light  and  half  shadow.  The  highest  light  and  deepest  shadow  come  in  immediate 
contact,  and  the  artist  has  so  adroitly  managed  to  diffuse  them  that  there  is  an  entire 
absence  from  those  patches  of  flatness  and  harsh  relief  which  give  what  is  called  hardness 
and  dryness  to  a  picture,  and  his  masses  are  everywhere  so  broken  by  variations  of  depth, 


168         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  lights,  as  well  as  the  figures,  should  *vary  iu  form.  This  depends  much 
upon  the  management  of  the  drapery.  In  the  infinitely  various  modes  of 
arranging  draperies,  the  artist  may  contract  or  extend  his  lights  at  pleasure, 
varying  the  general  effect  to  any  extent. 

71.  If  the  light  and  shade  in  a  picture  are  well  arranged,  and  in  due  quantity, 
the  effect  will  be  pleasing,  even  at  such  distance  from  the  eye  that  the  subject 
cannot  be  distinguished.  It  is  then  a  mere  correspondence,  or  a  balancing  of 
light  and  shade.  On  a  nearer  approach,  its  force  and  powerful  relief  attract 

that  while  there  is  no  baldness,  the  force  and  breadth  are  fully  preserved.  It  is  a  for- 
tunate circumstance  too,  that  his  points  of  greatest  force  and  interest  are  aboutthe  centre, 
and  all  die  off  nicely  as  the  outer  edges  of  the  work  are  reached,  for  it  is  generally  con- 
sidered that  busy  spots  of  light  and  dark  close  to  the  edges  or  in  the  corners  of  a  picture 
distract  the  attention  injuriously  to  the  main  central  effect.  How  the  poetic  grandeur 
of  the  scene  depicted  is  heightened  by  the  treatment  which  the  artist  has  given  it! — 
XANTHUS  SMITH. 

71.  In  the  department  of  art  known  under  the  general  name  of  genre,  especially  with 
simple  subjects,  the  photograph  may  be  more  successful,  though  the  best  specimens  that 
have  come  before  my  observation  have  been  immeasurably  inferior  to  the  same  kinds 
drawn  by  the  hand  of  real  masteis.  Genre  pictures  may  represent  scenes  in  open  air,  or 
they  may  be  interiors;  they  may  represent  action  or  repose,  animal  or  still  life;  but 
whatever  the  motive,  successful  treatment  requires  not  only  a  picturesque  arrangement, 
graceful  lines,  and  chiaroscuro,  but  a  harmonious  relation  of  parts  too  subtle  for  any 
instrument  but  the  thinking  brain  and  accommodating  hand.  Only  living  thought  can 
envelop  common  nature  in  that  atmosphere  of  poesy  without  which  any  picture  in  vain 
addresses  itself  to  the  mind;  without  this  divine  aid  the  most  judicious  selections  and 
poses,  secundem  artem  though  they  be,  fail  to  give  real  poetic  interest  even  to  objects  of 
beauty,  while  with  it  the  skilled  hand  gives  to  squalor,  poverty,  nay,  to  vice  itself,  an 
interest  or  pathos  which  appeals  to  the  finer  feelings  of  man  so  as  to  call  out  his  most 
delicate  sensibilities  and  sympathies.  This  is  art.  Rules  of  composition  in  art  form  no 
exception  to  rules  in  general.  They  are  simply  laws  which  reduce  the  imagination  to 
order  and  translate  its  visions.  Their  use  even  in  tasteful  groupings  from  nature  no 
more  produces  pictures  worthy  of  the  name  of  art,  than  a  strict  adherence  to  the  rules  of 
grammar  gives  birth  to  poems. 

Is  photography,  then,  incapable  of  producing  poetic  pictures?  No.  She,  too,  has  her 
possibilities.— L.  G.  SELLSTEDT. 

When  making  a  group,  the  principal  figure  should  receive  the  principal  light,  and  the 
picture  should  not  be  crowded  any  more  than  the  lens  in  use  compels.  If  the  group  be 
a  large  one,  it  should  be  broken  up  into  smaller  ones.  When  a  mass  of  people  are 
crowded  together  and  no  prominence  given  to  any  one  person,  or  any  number  of  persons 
divided  from  the  rest  with  reference  to  the  effect  of  gradation,  it  is  then  merely  grouping, 
and  not  composing. 

Figures  should  be  more  or  less  varied  in  attitude,  too,  because  exact  repetition  of  lines 


THE    APPLICATION    OF    ART    PRINCIPLES.  169 

the  eye,  and  fix  the  attention  of  the  spectator.  It  will  not  have  this  effect, 
unless  it  possesses  the  essential  requisites  of  chiaro-oscuro. 

72.  Having  now  considered  the  inside  principles  of  art,  so  to  speak,  such  as 
we  set  out  to  study  at  the  opening  of  the  chapter,  let  us  go  a  little  further  into 
the  depths  of  one  very  vital  point,  namely,  technique. 

One  may  be  armed  with  a  full  knowledge  of  art  principles ;  seized  with  a 
wholesome  fear  of  transgressing  the  laws  of  art ;  possessed  of  all  the  apparatus 
and  accessories  needful  to  produce  good  pictures ;  own  a  splendidly  arranged 
studio — and  yet  prove  a  miserable  failure  as  an  artist,  unless  careful  heed  is 
given  to  the  technical  requirements  of  his  work. 

73.  I  have  already  hinted  at  some  of  these,  but  the  lesson  cannot  be  made 
too  plain,  and  I  will  endeavor  to  push  it  further  home. 

As  a  word,  technique  is  an  art  term  rather  than  photographic  as  distinguished 
from  art,  but,  according  to  our  politics,  photography,  true  photography,  must 
be  and  is  and  ever  shall  be  art.  Therefore  after  all  technique  is  a  photographic 

produces  monotony  and  formality.  This  variation  should  be  governed  by  the  subject 
and  by  the  prominence  of  the  figures.  If  you  are  making  a  family  group,  although  the 
members  thereof  may  wish  the  baby  to  be  the  most  prominent  figure,  the  correct  way  is 
to  give  the  parents  the  leading  position,  and  around  them  group  the  rest  harmoniously. 
The  principles  of  nature  and  the  laws  of  art  both  frown  upon  making  the  figures  all 
equally  prominent. — M.  L.  DWIGHT. 

72.  Fit  it  with  such  furniture  as  suits 
The  greatness  of  his  person. 

It  shall  be  so  my  care 

To  have  you  royally  appointed,  as  if 

The  scene  you  play  were  mine. 

—  SHAKESPEARE. 

73.  Photography  is  a  true  daughter  of  art.  The  name  of  artist,  implying  technical 
skill  above  the  common  craftsman's,  a  dexterity  of  hand  guided  by  high  intelligence,  a 
glorious  marriage  of  manual  and  mental  excellency,  has  always  been  a  proud  and  honor- 
able one.  It  is  none  too  high  and  honorable  for  those  who  faithfully  follow  her.  Art 
meant,  originally,  handwork.  Painting,  now  so  haughty,  was  once  considered  simply  a 
superior  kind  of  artisanry,  as  some  would  have  our  art  now.  The  artist  in  colors  and  the 
artist  in  gold  or  glass  were  quite  on  a  footing.  Michael  Angelo  asked  only  the  title  of 
"  master-workman."  As  fine  art  with  pleasure  alone,  not  use,  its  object,  developed,  the 
idea  became  higher;  yet  still,  skilled  handwork  is  art.  Photography  is  surely  this. 
Indeed,  if  the  question  were  to  be  waged  on  definition  it  would  be  easily  won.  Kuskin 
himself  opens  a  gate  wide  enough  to  let  in  photography  with  all  her  tools  when  he  says 
art  is  the  "  expression  of  man's  delight  in  the  work  of  his  creator."  Hamerton  says  art 
is  "  selection ;  "  that  is  exactly  the  main  idea  of  good  photography. 


170        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

term,  and  we  may  use  it  without  being  considered  outlaws.  And  it  means 
workmanship — the  manner  in  which  things  are  done.  The  technique  of  a 
picture  is  its  drawing,  light  and  shade,  color,  and  perspective,  or,  more  plainly, 
their  management,  in  contradistinction  to  its  sentiments  or  ideas,  or  conception, 
if  you  will.  Given  a  gentleman  who  is  overly  fat,  or  who  has  an  inconsolable 
nose,  and  who  desires  a  photographic  portrait  made  to  hand  down  to  posterity 
that  will  show  his  deformities  of  size  and  shape  the  least.  He  is  willing  to  go 
to  some  trouble  and  expense  to  secure  the  fulfilment  of  his  desires,  and  therefore 
wisely  tries  several  photographers.  No  two  treat  him  alike,  but  in  whatever 
way  they  do  pose,  light,  and  generally  manage,  that  is  the  technique  of  their 
picture. 

74.  As  an  illustration,  "  Autumn,"  by  Mr.  F.  Granberry,  drawn  from  the 

But  suppose  painter  and  photographer  out  in  search  of  a  picture ;  with  equal  artistic 
perception  they  choose  a  scene,  a  bit  of  landscape.  Figures  and  accessories  are  posed 
and  arranged ;  and  they  will  find  the  photographer's  the  severer  examination  to  pass,  as 
his  work  must  be  done  before  the  execution  of  the  picture.  When  both  are  finished, 
although  the  painting  may  be  very  like  the  photograph,  save  in  its  colors,  yet  it  may 
claim  a  place  of  distinction  in  the  gallery,  while  the  aspirations  of  its  companion  may 
not  soar  above  the  parlor  table.  Where  did  their  ways  separate?  Where  did  this 
difference  begin  ?  "  With  the  first  stroke  of  the  brush,"  answers  the  unbeliever,  "  when 
the  painter  began  to  modify  crude  nature  by  his  art."  There  is  the  key  to  the  whole 
question.  "Nature  does  not  compose,  and  the  photographer  could  only  take  her  as 
she  is."  But  what  of  the  careful  choice  of  the  view-point,  the  posing  of  the  figures? 
Why  did  he  lop  off  that  branch  and  put  that  dark  stone  in  the  foreground  ? — F.  H. 
WILSON. 

74.  Daguerre  jogged  the  world  into  a  new  path ;  the  eyesight  of  the  people  was 
sharpened,  their  intellects  were  brought  to  a  focus  and  were  thrown  upon  nature,  the 
fountain-head  of  all  knowledge ;  the  reflection  back  upon  their  minds  gave  a  new  under- 
standing, a  command  of  thought,  of  ideas,  a  positive  knowledge  of  size,  shape,  light  and 
shade,  distance,  foreshortening,  perspective,  unity,  congruity,  and  placed  every  observer 
upon  a  pinnacle  from  which  to  survey  the  world,  hitherto  absolutely  unattainable. 
Everyone  became  an  embryo  artist,  and  as  this  new  faculty  did  not  interfere  with  the 
power  of  speech,  but  seemed  to  give  it  new  and  advanced  ideas  to  work  with,  the  powers 
of  description,  so  lacking  in  many,  began  to  feel  the  influence  of  the  hour,  and  good 
drawings,  good  descriptions  grew  so  fast  that  now,  at  this  day,  there  are  many  persons 
who  are  first-rate  writers  on  subjects  not  often  even  considered  by  those  previous  to 
Daguerre. 

A  man  who  can  see  no  faults  can  see  no  beauties.  His  ideas,  his  faculties,  his  ability 
to  think,  his  power  of  expression  even  seems  to  lie  dormant ;  he  is  a  stick,  a  log,  built  to 
be  an  active,  living  member  of  society ;  he  is  a  mere  clod,  he  has  innately  all  the 
machinery  of  mind  necessary  to  constitute  him  a  "man  of  mark,"  but  he  has  no  in- 


THE    APPLICATION    OF    ART    PRINCIPLES. 


171 


FIG.  173. 


painting  by  the  artist  himself,  will  serve  well  (Fig.  173).  The  technique  is 
magnificent.  The  lines  (which  you  now  understand  all  about)  of  the  leafy 
background  are  so  care- 
fully curved,  twisted,  and 
turned  as  to  make  the 
crisp  leaves  stand  out  in 
fine  perspective  just  as 
they  do  in  autumn  when 
the  tender  juices  of  sum- 
mer are  exhausted,  and 
they  begin  to  be  stiffened 
by  the  frosts  of  fall.  How 
rotund  is  the  fruit.  The 
peaches  and  the  plums 
turn  over  on  their  sides 
from  their  weight  of  rich- 
ness, and  the  grapes  lean 
over  against  one  another 
from  sheer  fatigue,  as 
though  the  juice  all  ran  over  to  one  side  like  the  weight  inside  a  Japanese 
puzzle-egg.  Now  if  the  leaves  hung  lank  and  limp,  and  the  peaches  and 
plums  stood  over  on  their  stem  ends.,  and  the  grapes  were  scattered  at  random 
here  and  there  over  the  floor,  we  should  say  that  the  destructiveness  of  winter 
had  begun  to  play  upon  them,  and  that  it  was  not  a  picture  of  "Autumn  " 
at  all.  The  technique  would  then  be  bad  enough — so  bad  that  even  the  admir- 
able light  and  shade  of  the  picture  would  be  without  avail. 

centive,  no  stirring  influence,  to  rouse  his  faculties  ;  he  is  a  mere  lucifer  match,  of  no 
earthly  use  till  some  one  rubs  his  back. 

Education  is  a  cultivation  of  the  faculties  with  which  we  are  amply  supplied.  Curiosity 
is  the  most  powerful  incentive  of  the  human  mind,  and  the  boy  who  is  constantly  asking 
questions  proves  his  possession  of  a  mind  which  demands  education  and  will  have  it,  and 
the  parent  who  is  able,  by  the  tendency  of  his  replies,  to  lead  the  boy  to  the  truth,  will 
never  feel  that  there  is  any  danger  of  a  wicked  tendency. 

Let  every  child  learn  observation ;  drawing,  by  directing  the  mind  to  minutiae,  best 
develops  that  faculty.  Pictured  illustrations  are  now  so  common  that  criticism  of  art  is 
universal,  and  as  a  picture  tells  more  in  a  few  square  inches  than  whole  pages  of  letter- 
press can,  let  us  encourage  pictures,  the  power  to  produce  them,  and  the  ability  to  discuss 
them  fairly  and  artistically.  I  give  Daguerre  the  whole  credit  of  inaugurating  this  great 
boon  to  mankind. — PROF.  S.  RUFUS  MASON. 


172        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


75.  A  picture  is  technically  good  if  it  gives  a  distinct  indication  or  impres- 
sion of  the  natural  model.      It  is  technically  incorrect  if  it  gives  us  false 
•pIG  174  information  as  to  the  shape  and 

form  of  nature,  or  such  shape 
or  form  as  is  transmitted  to  our 
brains  by  the  optic  nerves. 

The  next  illustration  is  from 
a  drawing  of  his  "  Return  from 
the  Ridotto,"  by  Mr.  A.  H. 
Baldwin  (Fig,  174).  The 
technique  is  so  bad  that  until 
we  are  told  it  is  a  Venetian 
lady  in  a  gondola,  we  could 
hardly  guess  the  conception. 

No  photographer  would  pose 
a  lady  in  this  manner,  for  he 
knows  full  well  that  he  would 
secure  such  enlargement  of  his 
fair  subject's  feet  as  to  bring 
down  on  his  head  her  eternal 
malediction.  Even  a  Venetian 
photographer,  with  a  subject 

•desiring  to  be  represented  pillowed  up  in  her  gondola,  perhaps  sick  with 
jealousy,  tired,  returning  from  a  ball,  would  scarcely  dare  pose  her  in  this  way 
lest  all  her  green-eyed  rage  fall  upon  him.  If  he  did,  his  technique  would  be 
bad. 

75.  We  sometimes  feel  that  photography  is  too  literal  to  be  artistic.  From  a  client's 
point  of  view,  its  tendency  is  to  exaggerate  the  imperfections  rather  than  the  perfections 
of  face  and  figure.  Should  you  have  a  stout  figure  to  photograph,  the  neck,  as  a  rule, 
will  appear  short.-  To  obviate  this  appearance  in  the  portrait,  it  is  best  to  adopt  a  stand- 
ing pose,  with  the  camera  a  little  below  the  level  of  the  head.  If  a  sitting  position  is 
chosen,  undue  height  will  be  given  to  the  shoulders,  and  the  shortness  of  the  neck  will 
be  emphasized.  In  treating  the  opposite  extreme — a  thin  figure  with  sloping  shoulders 
(not  so  objectionable  in  the  gentle  as  in  the  sterner  sex),  I  would  recommend  a  sitting 
pose,  and  in  the  case  of  a  gentleman,  especially  when  the  head  is  large,  a  little  drapery, 
in  the  form  of  an  overcoat,  loosely  thrown  back.  The  head  should  be  turned  in  the 
reverse  direction  from  the  angle  at  which  the  body  is  placed,  which  will  help  to  give  the 
appearance  of  substance  and  harmony  to  the  figure,  and  altogether  make  the  picture  more 
pleasing.— WM.  CROOKE. 


THE    APPLICATION    OF    ART    PRINCIPLES. 


173 


FIG.  175. 


A  much  better  specimen  of  technique  is  "  The  Courier/'  by  Mr.  C.  F.  Blau- 
velt.  (Fig.  1 75.)  Here  is  a  possible  picture  for  the  photographer  to  render  under 
his  skylight.  The  courier  is  duly 
accoutred  for  his  day's  work  of  guiding 
the  tourists  who  have  employed  him, 
through,  say,  the  noisy  streets  of 
Naples.  He  stands  at  the  stairway  of 
the  albergo  in  easy  attitude,  perhaps  con- 
versing with  some  of  his  party  above 
stairs  as  to  the  day's  pleasure.  The 
handling,  the  technique  in  pose,  in 
drawing,  in  light  and  shade,  in  per- 
spective, is  perfect.  Perfect  because 
there  is  a  true  rendering  of  the  pic- 
torial facts  of  nature,  so  far  as  the 
limitations  of  the  material  will  permit. 

An  untrue  rendering  would  be  bad 
technique.  You  need  but  turn  the 
man's  head  in  any  other  direction  than 
it  is  to  have  a  bad  rendering. 

76.  Now  we  leave  portraiture  for  a 
little,  and  step  up  to  a  class  of  subjects 

that  is  becoming  quite  the  rage  with  camera  lovers.    We  choose  for  our  pointer 
Edward  Moran's  breezy  picture  "Off  Cape  Hatteras."  (Fig.  176.) 

76.  A  work  of  art  is,  as  we  have  said,  an  expression  by  means  of  pictures  of  what  is 
beautiful,  and  the  points  to  gauge  in  a  picture  are  to  notice  what  a  man  wishes  to 
express,  and  how  well  he  has  expressed  it.  I  know  Switzerland,  and  love  it  well ;  but  I 
would  no  more  attempt  to  make  a  picture  of  a  peak  than  I  would  of  a  donkey-engine.  A 
peak,  shrouded  and  accentuated  by  aerial  turbidity,  and  just  peeping  into  an  Alpine 
subject,  might,  from  its  mystery  and  sentiment,  add  to  the  artistic  value  of  a  foreground 
subject.  But  the  usual  photographs  of  peaks  could  be  of  interest  only  in  a  Bsedecker. 
This  turbidity  can  be  well  rendered  in  a  photograph.  Painters,  as  we  do,  use  optical 
instruments,  such  as  Claude  glasses,  prisms,  and  the  camera  itself.  The  whole  point,  then, 
is  that  what  the  painter  strives  to  do  is  to  render,  by  any  means  in  his  power,  as  true  an 
impression  of  any  picture  which  he  wishes  to  express  as  possible.  A  photographic  artist 
strives  for  the  same  end,  and  in  two  points  only  does  he  fall  short  of  the  painter — in 
color,  and  in  ability  to  render  so  accurately  the  relative  values,  although  this  is,  to  a 
great  extent,  compensated  for  by  the  tone  of  the  picture.  I  here  use  the  word  in  its 
artistic  sense,  and  not  in  its  misused  photographic  sense.  How,  then,  is  photography 


174 


VriLSONJS    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  176. 


What  a  brilliant  effect  of  light  through  breaking  clouds  there  is  here — -just 

such  an  effect  as  one  naturally  ex- 
pects to  see  off  Cape  Hatteras  and 
at  kindred  spots.  And  what  a  sense 
of  motion  is  given  by  the  bellied 
waves,  the  rolling  vessel, 
cline  of  the  spars,  and  the 


the  in- 
'  noise  " 

of  the  clouds.  Here,  observe,  the 
same  rules  and  forms  of  composition 
are  followed  as  are  taught  for  por- 
traiture. If  the  picture  is  measured 
by  "feeling"  then  we  find  it  to 
come  up  fully  to  the  requirements. 
Is  there  not  a  feeling  of  "go  "  about 
it  which  is  most  charming  which 
would  be  gone,  if  the  wind  was 
hushed  and  the  masts  stood  straight 
and  the  water  was  calm  ?  It  is  a 
lovely  example  for  the  catcher  of 
marine  camera  views.  Rarely  can 
we  secure  such  admirable  technique 
There  are  a  few  good  reasons  for  this,  which 


in  our  instantaneous  views, 
can  only  be  partly  obviated. 


superior  to  etching,  wood-cutting,  charcoal  drawing?  The  drawing  of  the  lens  is  not  to 
be  equalled  by  any  man ;  the  tones  of  a  correctly  and  suitably  printed  picture  far  surpass 
those  of  any  other  black  and  white  process.  An  etching,  in  fact,  has  no  tones,  except 
those  supplied  by  the  printer.  As  I  have  said  before,  if  it  falls  short  anywhere,  it  is  in 
the  rendering  of  the  relative  values,  but  the  perfection  of  the  tone  corrects  this  in  a  great 
measure.  There  is  ample  room  for  selection,  judgment,  and  posing,  and,  in  a  word,  in 
capable  hands,  a  finished  photograph  is  a  work  of  art.  Again,  it  is  evident  that  the 
translation  of  pictures  by  photogravure,  for  the  same  reasons  given  above,  will  be  superior 
to  that  of  any  engraving.  But  we  must  not  forget  that  nine-tenths  of  photographs  are 
no  more  works  of  art  than  the  chromos,  lithos,  and  bad  paintings  which  adorn  the 
numerous  shops  and  galleries. 

Thus  we  see  that  art  has  at  last  found  a  scientific  basis,  and  can  be  rationally  discussed, 
and  that  the  modern  school  is  the  school  which  has  adopted  this  rational  view ;  and  I 
think  I  am  right  in  saying  that  I  was  the  first  to  base  the  claims  of  photography  as  a 


THE    APPLICATION    OF    ART    PRINCIPLES.  175 

77.  One  of  these  is  our  modern  plates.     And  our  drop-shutters  are  in  such 
a  hurry  that  we  catch  the  subject  between  breaths,  as  it  were,  and  do  not  secure 
the  sense  of  motion.     One  reason  of  this  is,  as  a  rule,  the  photographer  posts 
himself  upon  shore  and  points  at  his  models  from  their  sides.     An  end  or 
three-quarter  view  would  be  better.     The  only  difficulty  is  to  find  a  place  to 
post  the  camera.     From  a  long  pier  is  best.     But  we  are  trying  to  understand 
technique  now,  and  when  we  do  we  shall  the  better  secure  its  correct  rendering 
in  our  work. 

78.  One  more  example,  and  this  time  by  a  lady  :  the  "Amsterdam"  of  Miss 
Eliza  Greatorex.  (Fig.  177.)     With  our  eyes  blindfolded,  as  soon  as  the  name 

fine  art  on  these  grounds,  and  I  venture  to  predict  that  the  day  will  come  when  photo- 
graphs will  be  admitted  to  hang  on  the  walls  of  the  Royal  Academy. — PROF.  P.  H. 
EMERSON,  BA.,  M.B. 

77.  Modern  art  is  under  great  obligations  to  photography.     There  was  a  time  when  the 
artist  who  employed  the  camera  in  painting  pictures  was  regarded  as  a  person  who  made 
use  of  illegitimate  processes.     That  time  has  now  gone  by.     How  far  the  use  of  the 
camera  may  go  is  a  matter  that  depends  on  individual  bias  and  conscience.     A  mere 
mechanical  worker  in  paint  will  let  his  tools,  whether  camera  or  brush,  do  all  they  can 
for  him,  while  an  artist  will  always  hold  the  thing  expressed  higher  than  the  method  or 
vehicle  of  expression.     A  great  deal  of  what  appears  to  be  the  best  work  shown  at  our 
National  Academy  of  Design  is  primarily  camera  work.     That  is,  the  camera  has  been 
used  to  make  studies  or  photographic  sketches — to  seize  poses  or  expressions  that  are  too 
fleeting  to  be  grasped  by  the  brush  and  to  convey  general  impressions  of  parts  or  the 
whole  of  the  composition.     Here  the  legitimate  use  of  the  camera,  as  an  accessory  of 
easel  painting,  stops.    By  all  means  let  us  have  good  camera  pictures.    Let  us  work  from 
nature  with  the  camera  as  freely  as  with  the  brush,  but  do  not  let  us  attempt  to  make 
one  do  the  work  of  the  other.     Let  us  not  make  a  photographic  foundation  on  canvas 
and  then  color  it  with  oil  paint.     Honest  camera  work  is  a  good  thing,  and  the  time  will 
come  when  it  will  be  recognized  as  art.    Honest  brush  work  is  also  a  good  thing,  but  the 
union  of  the  two  with  intent  to  deceive,  only  brings  the  feeblest  side  of  each  process  to 
the  surface.     Artistic  insincerity  always  carries  its  penalty  with  it,  and  this  kind  of 
mongrel  work,  although  it  is  often  effective  at  first  sight,  is  rarely  satisfying  after  a  few 
glances  have  been  bestowed  upon  it. — CHARLOTTE  ADAMS. 

78.  A  true  photographer  seems  to  me  to  rank  with,  and  resemble,  the  troubadour  of  the 
middle  ages — poets  who  poured  out  their  impromptu  verses  to  the  call  of  the  audience. 
He  ought  to  be  a  reader  effaces — a  close  scrutinizer  of  the  inner  workings  of  the  subject 
before  him ;  catch  with  an  eagle  glance  the  peculiarities  of  gait,  the  tricks  of  motion ; 
and  be  gifted  with  the  rare  discrimination  which  can  separate  the  natural  habits  from 
the  society  affections.     I  think  a  photographer  ought  never  to  be  in  the  studio  when  the 
Bitter  first  enters.     He  or  she  ought  to  be  left  a  little  time  alone,  or,  rather,  a  special 


176         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Amsterdam  is  heard  we  could  almost  formulate  the  technique  of  any  good 
picture  of  it  in  our  minds.  We  should  expect  no  rocky  banks  with  sea  birds 
resting  in  the  crevices,  or  foregrounds  rich  in  clover  or  daisies  or  fields  of 
golden  grain.  Neither  lines  of  tall  oaks,  or  castled  crags  hiding  the  blue  sky 

FIG.  177. 


from  our  view.  On  the  contrary,  we  should  begin  to  picture  what  the  fair 
artist  has  so  finely  represented  by  her  splendid  workmanship,  a  foreground 
broad  in  water,  with  bits  of  turf  here  on  the  left,  and  a  city  whose  sunken- 
down-into-the-lagoon  effect  is  accentuated  by  the  low  line  of  the  horizon  and 
the  unusual  height  of  sky.  And  how  she  gives  charming  variety  of  light  and 
shade  in  masses  arranged  with  feminine  subtlety  by  the  deft  manipulations  of 
the  brush. 

I  have  used  the  word  technique  broadly,  as  covering  the  whole  construction 
of  the  picture,  rather  than — in  the  narrower  interpretation  of  the  painter — the 
mere  brush  work.  For  if  there  is  one  subject  above  another  which  photo- 
artists  want  more  light  on,  it  is  their  technique. 

The  artist  who  attends  to  all  of  the  technical  details  in  his  work  need 
not  necessarily  resort  to  artificiality.  He  believes  that  the  highest  art  should 

chamber  ought  to  be  set  apart  where  the  sitter  may  enter,  with  attractive  objects  to 
attract  the  attention  placed  about  the  room,  while  the  artist,  for  a  few  moments,  from  an 
unseen  point,  may  watch  and  study  his  subjects  when  they  think  themselves  unobserved; 
afterward  let  an  employe"  enter  and  address  the  sitter  while  he  still  watches  from  his 
point  of  observation,  by  which  means  he  may  judge  and  learn  what  the  sitter  is  in  a 
natural  state  alone  and  the  sitter  in  society.  And  so  he  may  wait,  after  the  instantaneous 
plate  is  in  the  camera,  for  the  moment  when  the  sitter  unconsciously  looks  natural,  to 
flash  the  light  upon  her ;  indeed,  I  have  thought  if  the  studios  could  be  so  constructed 


THE    APPLICATION    OF    ART    PRINCIPLES.  177 

always  hold  a  soul  of  truth  within  its  body  of  beauty.  The  body  may  be 
never  so  beautifully  rendered,  if  the  soul  of  truth  is  obscured.  If  the  likeness 
is  gone,  the  beauty  is  also  departed.  And  likeness  does  not  consist  alone  in 
the  counterfeit  presentment  of  the  body.  As  much  as  possible,  the  carriage  of 
the  body  and  of  the  head  must  be  as  nature  controls  it,  but  quick,  like  a  flash, 
at  sight  almost,  the  artist  must  not  only  discern  the  temper  of  the  man  but  he 
must  deftly  bring  the  very  scintillations  of  the  soul  beaming  out  upon  the 
face.  He  must  make  them  create  the  delicate  elevations  and  depressions,  curves 
and  lines,  which  make  up  the  modulations  of  the  flesh,  and  while  they  catch 
the  light  and  receive  the  shadows  under  the  lighting  he  has  arranged,  they  must 
be  seized  upon  his  sensitive  plate.  And  is  his  work  done  then  ?  No.  He 
must  repair  to  the  darkness  lest  the  very  element  which  helped  him  should 
destroy  all.  Then  there,  with  wondrous  patience  while  with  agile  hand  he 
pours  the  potent  lotions  upon  his  plate,  he  watches  and  applies,  and  retards, 
and  accelerates,  and  moulds  and  forms,  as  the  painter  with  his  brush,  as  the 
potter  with  his  clay,  and  with  brains  alert,  until  lo  !  the  man,  in  the  likeness 
of  his  own  image.  His  eye  for  the  beautiful,  guided  by  his  love  for  the 
beautiful,  has  enabled  him  to  bring  out  the  beauties  of  the  soul  of  the  man 
upon  his  face,  and  thus  he  is  a  promoter  of  refinement  of  the  highest  type. 
The  man  who  sends  out  a  bad  picture  into  the  world  is  a  doer  of  evil.  If  he 
is  a  poet  and  a  true  artist  he  will  never  permit  that. 

He  must  be  as  a  magician  who,  from  sources  unobserved  and  not  understood 
by  others,  brings  out  the  soul  and  spirit  upon  the  face. 

One  has  written  as  to  the  poet,  "  If  he  leave  the  body  untenanted,  it  is  well, 
for  it  is  a  body  of  beauty ;  if  he  beckon  in  an  angel  of  light,  it  is  noble,  and  he 
has  done  well  for  his  kind ;  if  the  devil  of  darkness  have  taken  possession  at 
his  word,  he  has  earned  for  his  name  a  place  on  the  scroll  of  the  enemies  of 
our  race."  It  .is  precisely  so  with  the  artist — if  he  be  a  true  artist. 

And,  as  I  have  said,  what  a  magician  he  must  be,  since  during  the  day  he 
must  originate  some  means  of  developing  visibly  what  soul  he  intuitively  feels 
must  have  existed  within  the  beauty  of  the  bodies  presented  before  his  camera. 

that  the  operator  need  never  enter  the  room  at  all,  but  have  the  camera  so  adjusted  from 
an  outside  room  that  the  sitter  might  not  know  the  moment  they  were  taken,  it  would 
be  best— for,  to  me,  naturalism  is  always  before  even  a  first-class  sighted  likeness; 
however,  if  the  photographer  knows  the  peculiarities  of  his  sitter,  and  these  be  comely 
peculiarities,  he  will  pose  so  as  to  bring  them  sufficiently  out  for  his  purpose. — HUME 

NlSBET. 

12 


178         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

79.  "Originate?  Can  there  be  anything  original  in  photography?"  it  has 
been  asked  over  and  over  again.  Do  not  the  workmen  of  this  guild  all  have 
the  same  tools  of  light  and  shade  to  build  up  the  image  upon  the  sensitive  plate  ? 
Verily,  but  originality  does  not  consist  in  swinging  them  at  random  until  their 
trickery  astonishes  you  by  the  maudlin  results.  Nature  must  be  rendered 
truthfully  and  yet  surprisingly.  The  elements  of  character  held  dear  by  rela- 
tives and  friends  must  be  not  only  secured,  but  with  a  degree  of  refined  intensity 
that  will  make  them  appear  more  lovely  in  the  picture  than  they  are  seen  even 
in  nature.  No  two  persons  see  alike.  It  is  a  rare  thing  for  both  eyes  of  one 
person  to  see  exactly  alike.  Remembering  this,  the  quick  artist  seizes  upon 
the  elements  of  character  which  he  sees  and  adroitly  brings  them  to  the  surface. 
He  cannot  tell  how  any  more  than  the  orator  can  tell  you  how  he  holds  his 
audience.  He  can — he  does — and  therefore  he  is  an  inventor,  an  artist.  No 
more  passes  before  his  eyes  than  before  others,  but  he  perceives  more,  because 
his  mind  is  more  susceptible.  How  many  thousands  and  tens  of  thousands 
could  say  that  they  had  seen  the  lovely  effects  of  light  and  shade,  which  Master 
Rembrandt  painted  with  such  effect,  after  he  had  placed  them  in  rich  masses 

79.  As  mechanical  photography  deals  with  material  beauty,  so  let  art  photography 
treat  with  intellectual  beauty ;  and  when  deep  and  earnest  minds,  seeking  to  express 
their  ideas  of  moral  and  religious  beauty,  employ  high-art  photography,  then  may  we  be 
proud  of  our  glorious  art,  and  of  having  aided  in  its  elevation.  And  where  does  art 
come  in  ? 

You  may  find  this  query  admirably  answered  in  a  beautiful  poem  by  Mr.  Longfellow, 
entitled  "Ke>amos,"  which  is  none  other  than  the  history  of  the  ceramic  art,  and  which 
beautifully  closes  as  follows : 

"Art  is  the  child  of  Nature  ;  yes, 
Her  darling  child,  in  whom  we  trace 
The  features  of  the  mother's  face, 
Her  aspect  and  her  attitude, 
All  her  majestic  loveliness 
Chastened  and  softened  and  subdued 
Into  a  more  attractive  grace, 
And  with  the  human  sense  imbued. 
He  is  the  greatest  artist,  then, 
Whether  of  pencil  or  of  pen, 
Who  follows  Nature.     Never  man 
As  artist  or  as  artisan, 
Pursuing  his. own  fantasies 
Can  touch  the  human  heart,  or  please, 
Or  satisfy  our  nobler  needs 
As  he  who  sets  his  willing  feet 
In  Nature's  footprints,  light  and  fleet, 
And  follows  fearless  where  she  leads." 

So  let  us  walk  and  work  and  live  in  Nature's  footprints. — EDWARD  L.  WILSON. 


THE    APPLICATION    OF    ART    PRINCIPLES.  179 

of  harmony  upon  his  canvas,  but  none  revealed  their  charms  before  him.  Why 
do  we  fall  back  overcome  with  emotion  when  we  enter  the  stanzes  of  Raphael 
in  the  Vatican  ?  It  is  because  he  saw  so  much  more  in  a  human  face  than  we 
can,  and  could  translate  it  into  paint  upon  canvas  with  feeling  which  we  do  not 
have.  But,  like  a  puzzle,  we  can  partly  understand  it  when  it  is  put  before  us 
even  in  such  a  bewildering  way. 

The  objects  then  are  given  to  all  of  us  to  see.  But  the  power  of  perceiving 
the  soul — man — of  bringing  it  out  upon  the  face,  is  reserved  for  the  mind  of 
the  true  artist.  And  the  photographer  may  be  a  true  artist. 

Painters  usually  are  loath  to  permit  photographers  to  make  any  claim  to 
artistic  merit.  Their  works  are  crowded  out  of  exhibitions  and  collections, 
because  they  are  not  considered  as  the  productions  of  art.  Those  who  paint, 
those  who  cut  and  carve,  however,  are  becoming  more  reconciled  to  the  thought 
of  allowing  photography  to  walk  alongside,  and  are  becoming  more  lenient  than 
they  were.  Doubtless  they  begin  to  feel  that  our  art  is  a  necessity  to  theirs. 
It  is  art,  and  an  incomparably  expeditious  one.  Where  is  the  painter  or 
sculptor  who  would  not  quail  at  the  thought  of  reproducing  such  lively  repre- 
sentations of  nature  as  are  produced  by  our  blessed  art,  in  the  same  time  ?  The 
subject  is  presented  to  the  photographer,  grumbling  and  growling  and  com- 
plaining and  fretting  because  of  the  unpleasantness  of  sitting  for  a  photograph, 
and  our  artist  is  expected  in  the  few  moments  at  his  command  to  produce  the 
most  lifelike  counterfeit  that  the  exactions  of  an  impatient  nature  can  claim ; 
while  the  painter  or  the  sculptor  is  permitted  to  have  ten  times  as  many  sittings, 
each  ten  times  as  long,  with  no  complaint  and  no  rebellion.  Who  then  is  the 
greatest  artist  but  he  who  produces  the  most  natural  result  in  the  shortest  time  ? 

80.  And  not  only  is  all  this  expected  from  him,  but  he  is  likewise  held  more 
or  less  responsible  for  the  expression  of  his  subjects. 

80.  When,  fifty  years  ago,  the  new  baby,  Photography  $  was  born,  Science  and  Art 
stood  together  over  her  cradle,  doubting  what  they  might  expect  from  her,  wondering 
what  place  she  would  take  among  their  other  children.  Science  soon  learned  that  she 
had  come  with  her  hands  full  of  gifts,  and  her  bounty  to  astronomy,  microscopy, 
chemistry,  made  her  name  blessed  among  these  her  elder  sisters.  Art,  always  more 
conservative,  hung  back.  The  gifts  at  first  were  fewer,  and  she  seemed  an  ominous  rival 
to  the  others.  She  threatened  to  leave  them  nothing  to  do.  But  slowly  jealous  Art,  who 
first  frowned  and  called  the  rest  of  her  brood  around  her  away  from  the  parvenue,  has 
let  her  come  near,  has  taken  her  hand,  and  is  looking  her  over  with  questioning  eyes. 
Soon,  without  a  doubt,  she  will  have  her  on  her  lap  with  the  rest. 

Why  has  she  been  kept  out  so  long  ?     Almost  from  the  beginning  she  claimed  a  place 


180 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


Some  time  ago  the  noted  French  scientist,  Chevreul,  reached  the  age  of  one 
hundred  years.     La  Nature  devoted  the  entire  space  of  an  issue  to  a  series  of 


FIG.  178. 


photographic  interviews  with  the  scientist,  in  which,  while  the  famous  Parisian 
photographer,  M.  Paul  Nadar,  conversed  with  him,  a  stenographer  took  the 

in  the  house  beautiful  of  art.  In  spite  of  rebuffs  she  knocked  at  its  doors,  though  the 
portrait  painter  and  the  critic  flung  stones  at  her  from  the  house-top,  and  the  law  itself 
stood  at  the  threshhold  denying  her  entrance.  Those  early  efforts  were  not  untinctured 
with  a  fear  that  if  she  did  get  in  she  would  run  the  establishment ;  but  the  law  long  since 
owned  her  'right,  and  instead  of  the  crashing  boulders  of  artistic  dislike  and  critical 


THE    APPLICATION    OF    ART    PRINCIPLES.  181 

conversation  and  an  operator  a  series  of  instantaneous  photographs  of  the  two 
noted  personages.  These  so  set  forth  the  variety  and  quickness  of  the  changes 
of  human  expression  that  I  add  a  selection  of  them  here  (Fig.  178),  with  some 
suggestions  as  to  what  feelings  the  different  expressions  in  conversation  may 
indicate:  1.  Amusement;  2.  Argument;  3.  Disclaimer;  4.  Challenge;  5. 
Doubt;  6.  Attention;  7.  Triumph;  8.  Seeing  is  believing;  9.  Profundity. 

When  my  practical  readers  are  told  by  their  patrons  "  I  never  looked  like 
that ! "  these  phases  may  serve  to  prove  that  the  camera  catches  exactly  and 
truthfully  whatever  comes  before  it  at  the  moment  of  exposure. 

indignation  the  volleys  that  drop  at  her  feet  now  are  mere  mossy  pebbles  flung  by 
similarly  mossy  critics  or  artist-bigots.  Still  the  world  at  large  hears  them  rattle,  and 
does  not  yet  give  her  the  place  and  estimation  she  has  won. — F.  H.  WILSON. 

Art  began  with  the  first  touch  of  a  man  to  shape  things  toward  his  ideal,  be  that  ideal 
merely  an  agreeable  composition  or  the  loftiest  conception  of  genius.  The  higher  it  is 
the  more  it  is  art.  Art  is  head-and-hand-work,  and  a  creation  deserves  the  name  of  art 
according  to  the  quantity  and  quality  of  this  expended  on  it.  Simply  sit  down  squarely 
before  a  thing  and  imitate  it  as  an  ox  would  do  if  an  ox  could  draw,  with  no  thought  or 
intention  save  imitation,  and  the  result  will  cry  from  every  line,  "  I  am  not  art,  but 
machine  work,"  though  its  technique  be  perfection.  Toil  over  arrangement  and  meditate 
on  point  of  view  and  light,  and  though  the  result  be  the  rudest,  it  will  bear  the  impress 
of  thought  and  of  art.  I  tell  you  art  begins  when  either  man,  with  thought  forming  a 
standard  of  beauty  in  his  mind,  commences  to  shape  the  raw  material  toward  it.  In 
pure  landscape,  where  modification  is  limited,  it  begins  when  the  artist  takes  one  stand- 
point in  preference  to  another.  In  figure  composition,  where  modification  is  infinite,  it 
begins  with  the  first  touch  to  bring  the  model  into  pose.  When  he  bends  a  twig  or 
turns  a  fold  of  drapery,  the  spirit  of  art  has  come  and  is  stirring  in  him.  What  matters 
hia  process?  Surely  it  is  time  this  artistic  bigotry  was  ended. — F.  H.  WILSON. 


CHAPTEE    X. 

OUTDOOR   OPERATIONS. 

81.  THE  student  has  already  discovered  that  the  same  principles  and  laws 
which  should  influence  the  photographer  under  the  skylight,  should  be  per- 
mitted to  have  even  fuller  sway  when  working  under  the  broad  canopy  of 
heaven. 

There  are,  however,  some  special  lessons  needed  by  the  out-door  worker, 
which  it  will  be  the  purpose  of  this  chapter  to  suggest. 

The  choice  of  subject  being  made,  if  there  is  time  for  deliberation  its  com- 
position should  be  carefully  studied.  Then  Old  Sol  should  be  consulted  as  to 
what  time  of  day  he  can  be  relied  upon  to  give  the  best  light  upon  your  choice. 

These  points  are  all-important. 

With  emergent  cases,  such  as  subjects  on  the  way,  "  snap  shots  "  and  "  hit 
or  miss  "  chances,  of  course  there  is  no  time  to  deliberate ;  but  there  is  always 
a  choice:  Be  greedy,  and  take  the  best. 

A  hint  or  two  as  to  this. 

81.  It  does  not  always  require  a  grand  scene  of  rock,  river,  and  mountain,  to  make  up 
a  picture.  Very  simple  things,  which  a  person  not  accustomed  to  observe  would  pass  by 
unnoticed,  will  in  the  hands  of  one  who  has  the  knowledge  and  tact  to  properly  picture 
them,  be  made  very  attractive  and  artistic  too. 

Small  bits  of  landscape  I  would  advise  as  preferable  for  the  beginner  as  being  more 
simple,  and  a  variety  of  composition  and  effect  can  be  produced  with  greater  ease  and 
simpler  means. 

The  foreground  being  one  of  the  main  points  in  a  picture,  and  generally  required  to 
be  bold  and  effective,  can,  if  not  naturally  so,  be  made  so  in  a  great  measure  by  a  little 
labor  in  the  way  of  rolling  up  an  old  log  or  stump  in  an  effective  position,  or  placing  a 
bush  or  clump  of  large-leaved  weeds  where  they  will  be  of  service  in  making  a  proper 
balance  or  contrast  as  may  be  needed. 

And  let  me  advise  you  here  to  always  have  with  you  on  your  photographic  trips,  a 
spade  and  a  good  axe;  the  latter  particularly  will  often  be  found  "a  friend  in  need," 
when  it  is  desirable  to  cut  a  small  tree  or  remove  a  branch  that  would  otherwise  obscure 
some  important  point  of  your  view. — JAMES  MULLEN. 
(182) 


OUTDOOR    OPERATIONS. 


183 


82.  You  are  out  with  your  camera  as  eager  to  gather  some  food  for  it  as  a 
hungry  lion  prowling  about  seeking  whom  he  may  devour.  Thank  you  for 
your  enthusiasm.  It  is  FlG  .,  79 

one  of  the  first  requi- 
sites. 

By  the  roadside, 
ahead,  long  before  you 
reach  them,  you  are 
attracted  by  some  fine 
trees,  and  you  deter- 
mine to  gather  them 
in.  You  observe  that 
the  light  is  against  you, 
but  the  other  side  must 
be  just  as  beautiful,  and 
you  climb  over  the 
fence  into  the  meadow 
for  your  view.  Some  patient  cattle  are  there  chewing  their  cuds.  The  light 
is  lovely,  but  the  meadow  inclines  toward  the  sun,  and  your  proper  standpoint 
gives  an  ugly  foreground.  Instinctively  your  art  principles  come  to  your  help 
and  (mentally)  you  offer  your  kingdom  for — a  cow.  You  drive  her  down  to 
where  she  is  most  needed,  and  your  result  is  as  artistic  as  "  A  Landscape/' . 
by  Mr.  Wiuslow  Homer  (Fig.  179),  because  you  have  broken  up  the  monoto- 
nous foreground  by  the  aid  of  the  cow. 

82.  As  we  advance  to  scenes  fuller  of  interesting  natural  objects,  we  have  less  need  of 
incident  to  give  interest.  Distant  mountains,  with  a  river  or  lake,  fine  trees  and  rocks, 
go  to  make  up  the  sum  of  a  beau  ideal  landscape,  and  when  we  can  get  the  mountains 
and  water  near  the  centre,  with  a  fine  large  group  of  trees  on  one  side  and  a  lesser  group 
of  trees  or  rocks  upon  the  opposite,  we  have  the  most  complete  arrangement.  And  it  is 
not  necessary  that  the  features  should  be  large  or.  the  scenery  on  a  very  grand  scale,  for 
where  there  are  no  figures  or  buildings  by  which  to  measure  the  comparative  size,  scenes 
composed  of  smaller  features,  well  disposed,  make  just  as  good  pictures,  and  to  my  fancy 
sometimes  better,  because  in  the  case  of  the  large  scenery,  there  being  generally  no  means 
of  measuring,  one  is  not  impressed  with  the  grandeur,  as  he  would  be  in  the  presence  of 
the  scene  itself.  And  with  small  features,  provided  they  are  picturesque,  there  is  more 
rural  poetic  sentiment,  more  variety,  and  the  proper  point  for  the  forming  of  an  agreeable 
picture  is  more  easily  obtained. 

It  is  true  that  some  painters  often  took  great  liberties  with  views,  and  in  order  to  carry 
out  their  bent  so  changed  not  only  the  proportions  of  important  objects,  but  their  true 


184       WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


FIG.  180. 


83.  If,  instead  of  a  meadow,  a  river  forms  your  foreground,  as  we  see,  for 
example  in  the  painting  of  the  "  Bouquet  River  in  Winter/7  by  George  B. 

Wood,  Jr.  (Fig.  180), 
you  could  not  break  it 
up,  unless  it  be  by  a 
broad  mass  of  light  such 
as  the  daring  artist  has 
used  in  his  picture. 

Most  careful  atten- 
tion should  always  be 
given  to  the  foreground. 
Even  though  it  is  neces- 
sary to  place  an  old 
stump  or  a  log  or  a  cow 
there,  rather  do  it  than 
allow  it  to  be  monotonous.  Good  lessons  on  this  score  may  be  had  by  studying 
the  illustrations  which  follow.  Attention  to  light  and  shade,  balance  and 
harmony,  and  composition,  is  what  gives  one  landscape  photographer  better 
success  than  his  competitor. 

relative  position  with  regard  to  each  other,  as  to  make  the  picture  almost  unrecognizable 
as  a  view  of  the  place  it  was  intended  to  represent;  but  the  photographer  need  never 
have  the  slightest  fear  of  falling  into  error  in  this  direction,  as  his  views  must  necessarily 
be  always  too  realistic  and  matter  of  fact,  and  exaggeration  of  the  picturesque,  in  exam- 
ples, can  do  him  no  harm.  Besides,  such  study  will  be  a  great  aid  to  him  in  making  his 
selections,  first,  of  the  kind  of  objects  or  scenes  most  worthy  of  his  attention;  and, 
secondly,  of  the  most  proper  point  of  view  from  which  to  seize  all  the  salient  points  and 
to  take  them  in  the  most  harmonious  and  agreeable  manner. — XANTHUS  SMITH. 

83.  If  you  have  time  reconnoitre  the  place  previous  to  working.  Pick  out  your  stand- 
point, and  look  out  for  what  will  make  views ;  mark  down  the  time  of  day  the  light  is 
most  suitable.  In  this  way  you  can  start  in  the  morning  with  your  traps,  keeping  the 
sun  two-thirds  or  three-quarters  on  your  work,  and  follow  him  all  day,  except  for  strong 
cloud  or  moonlight  effects.  For  these  you  will  require  a  box  with  the  lid  over  your 
lenses,  and  will  have  to  work  directly  towards  the  sun.  Watch  until  the  sun  is  capped 
on,  the  edge  by  a  cloud,  and  then  expose  for  one  or  two  seconds  for  the  clouds.  Then 
close  the  lid  half  down,  and  keep  slightly  moving  it  up  and  down  between  the  horizon 
and  foreground  for  detail  in  the  picture.  As  a  general  thing,  this  class  of  views  is  in- 
tended-more for  cloud  effects  than  a  picture  full  of  details  or  half-tones.  The  best  moon- 
light effects  are  got  near  sunset;  then  you  have  to  work  almost  instantaneously. 

My  latest  mode  of  working  is  to  give  a  good  exposure  for  details ;  and,  in  developing, 
get  out  all  you  can,  but  do  not  overexpose  or  develop  so  as  to  get  a  foggy  or  flat  negative. 


OUTDOOR    OPERATIONS. 


185 


FIG.  181. 


84.  The  introduction  of  water  is  always  desirable,  if  it  is  possible.     It  not 
only  affords  variety  to  the  subject,  but  it  supplies  light  and  snap  to  a  picture 
as  a  rule. 

Xo  more  charming  bits  for  the  camera  can  be  found  than  those  which  are 
offered  by  the  lovely  tree-lined  brooks,  lakes,  and  rivers  of  our  country. 

The  low  sun  is  usually  best  for  such  subjects,  when  the  light  enters  horizon- 
tally and  diffuses  itself  among  the  shadows  of  the  foliage.  There  is  great 
room  for  choice  here — the  greatest  room. 

85.  If  mountains  are  in  the  distance  and  you  desire  to  secure  atmospheric 
effect,  such  as  we  see  in  the  charming  "  Lake  Leman  "  of  Mr.  J.  H.  Casilear 
(Fig.  181),  then  a  little 

sacrifice  of  principle  is 
allowable  so  as  to  secure 
a  good  expanse  of  water 
in  the  foreground,  at  right 
or  left.  Then  variety  may 
be  secured  and  the  atmos- 
pheric effect  assisted  by 
selecting  a  point  where 
rocks,  trees,  or  a  part  of 
the  beach  or  a  boat  at  anchor  may  be  included.  If  the  external  atmosphere  is 

For  general  work  a  well-lighted  picture  will  not  require,  if  your  chemicals  are  in  good 
working  condition,  any  redeveloping  or  intensifying. — B.  W.  K. 

84.  In  a  river  view  strive  to  get  a  good  mass  on  either  one  side  or  the  other  of  the 
subject,  and  do  not  let  it  extend  far  enough  into  the  picture  to  cut  off  too  much  of  the 
distance,  if  the  latter  is  good.    If  there  should  be  so  much  of  interest  in  a  side  group  that 
you  must  extend  it  very  far  across  the  plate,  make  it  the  subject,  sacrificing  the  rest. 
When  you  have  a  fine  side  group  of  trees  with  a  good  profile,  an  agreeable  combination 
of  curves,  straight  passages,  and  angles,  for  instance,  do  not  cut  the  top  off  it,  but  let 
some  sky  appear  above,  by  retiring  further ;  or  if  this  is  not  practicable,  using  a  wider 
angle  lens.     In  other  instances,  where  there  is  a  high  blank  wall  of  uninteresting  or 
monotonous  foliage,  with  a  very  interesting  passage  of  stems  underneath,  then  advance 
closer,  cut  off  much  of  the  top,  and  aim  for  one  of  those  pretty  compositions  in  which  a 
passage  of  distance  is  seen  beneath  overhanging  or  overspreading  boughs.    The  deep, 
quiet  passages  of  shadow  cast  upon  the  earth  under  spreading  trees  give  breadth  and 
effect  to  a  subject,  and  when  it  happens  that  a  stump,  or  rock,  or  cow,  or  some  such  object 
can  be  relieved  in  high  light,  by  being  a  little  nearer  and  cutting  against  such  mass  of 
shadow  the  effect  is  greatly  heightened. — XANTHUS  SMITH. 

85.  A  considerable  amount  of  atmosphere  will  be  found  of  advantage  in  extended  river 


186 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  182. 


in  proper  condition,  the  time  of  day  and  light  agreeable,  and  the  water  calm, 
lovely  reflections  may  be  caught  as  we  see  them  in  Mr.  E.  C.  Minor's  poetic 

view  of  "  Evening  "  (Fig. 
182).  I  have  more  than 
once  waited  an  hour  for 
the  water  to  calm  and  for 
the  sun  to  move  where  I 
wanted  it,  in  order  to  se- 
cure such  a  choice  as  this. 
86.  But  we  cannot 
have  one  favor  without 
yielding  another,  and  so, 
sometimes,  to  get  reflec- 
tions like  this  we  must 
break  the  rules. 

scenes,  as  it  separates  different  passages,  causing  the  more  distant  to  recede,  thereby 
adding  to  the  look  of  perspective  or  retiring  of  the  distance ;  and,  moreover,  it  gives 
mystery,  which  is  an  agreeable  quality  in  art.  It  is  of  great  advantage  to  have  calm,  or 
very  nearly  calm,  water,  the  reflecting  of  passages  of  deep  shadow  preventing  too  sharp 
cutting  of  shore  lines,  and  also  removing  the  difficulty  of  the  whole  water  in  the  picture 
being  a  cut-out  light  patch  of  equal  brightness  all  over.  It  is  a  fortunate  time  if  water 
can  be  got  perfectly  calm  under  hills  or  rocky  bluffs,  with  their  deep,  quiet  reflections 
underneath,  and  streaked  by  puffs  of  air,  causing  strips  of  bright  light,  making  it  appear 
more  level.  Boats  or  skiffs  are  a  great  improvement  in  water  scenes  if  they  happen  to  be 
in  a  fortunate  position.  In  the  middle  distance  they  measure  the  size  of  the  scene,  by 
comparison,  and  as  foreground  features,  with  their  deep  touches  of  shadow  form  good 
points  of  interest,  but  will  always  be  preferable  if  not  full  side  view  or  directly  end  on. — 
XANTHUS  SMITH. 

86.  To-day,  while  I  write,  the  air  is  as  clear  as  in  the  White  Mountains  in  June,  and 
as  mild  as  Newport  at  the  same  season;  out  of  my  window  are  the  vivid  green  meadows 
of  the  "  garden  of  England,"  here  and  there  dashed  with  clouds  of  daisies  and  buttercups  ; 
the  trees  in  their  tender  first  green,  with  silvery  willows  and  hedgerows  of  hawthorn  like 
green  waves  on  a  green  sea  breaking  into  foam  of  blossom.  In  the  distance,  the  rolling 
downs  with  great  golden  drifts  of  gorse  come  up  against  the  sky,  blue,  almost  cloudless, 
but  with  a  misty  tenderness  which  we  so  rarely  find  in  the  American  half  of  the  blue 
expanse. 

I  look  out  of  my  window  and  despair  of  photography,  it  gives  so  little  of  all  that  is 
most  entrancing  in  nature.  But  a  little  glimpse  here  and  there  is  my  consolation ;  a 
farm-yard,  just  seen  amongst  the  towering  elms ;  a  bit  of  a  lane  where  the  trees  over- 
arch, and  where  we  may  sometimes  catch  a  carter  with  his  heavy  train,  and  stop  him 


OUTDOOR    OPERATIONS. 


187 


The  more  strictly  artistic  composition  is  found  in  another  painting  by  Mr. 
Casilear,  "  A  Scene  in  New  Hampshire"  (Fig.  183).     The  group  of  n'jble 


FIG.  183. 


elms,  the  alders  close  to  the  river,  the  shrubs  on  the  right,  and  the  stony  bottom, 
give  us  a  pleasant  variety  for  an  unbroken  foreground.  Then  comes  the 

long  enough  to  get  the  pose ;  a  nook  of  green  field  where  the  brook  borders  it,  with  flag 
and  wild  flowers  rich  in  details  of  vegetation.  These  crumbs  of  comfort  fall  to  me  from 
the  broad  table,  and  I  am  consoled  that  though  the  higher  motives  are  to  be  realized 
only  by  the  infinite  labor  of  art  and  the  complications  of  the  palette,  I  can  render  justice 
to  some  of  the  qualities  of  these  minor  beauties,  such  as  no  man  can  give  with  the  pencil ; 
and  if  it  were  not  for  my  duty  to  the  Philadelphia  Photographer  I  should  be  to-day  on  a 
cruise  amongst  the  farm-yards,  and  nooks  and  corners  aforesaid,  with  the  comfortable 
satisfaction  of  trustworthy  dry  plates  and  a  Scovill  Company's  dry-plate  box,  knowing 
that  I  have  a  dozen  and  a  half  chances  for  a  picture  on  the  full  size  of  my  plate. — W.  J. 
STILLMAN. 

The  ability  to  climb  is  one  to  be  cultivated  by  the  would  be  successful  mountain  pho- 
tographer. A  great  many  pictures  I  have  seen  made  in  mountain  regions  are  imperfect 
and  unsatisfying,  because  the  camera  was  placed  at  too  low  a  standpoint. 

The  foregrounds  are  filled  with  incongruous  and  badly  composed  rocks,  or  trees,  or 
roadway  it  may  be,  and  there  is  no  feeling  of  atmosphere  or  distance  whatever,  though  it 
is  true  there  are  the  mountains  in  the  beyond. 

To  correct  these  evils  you  must  climb — climb  to  a  point  where  you  can  overlook  the 
immediate  foreground,  and  secure  a  good  expanse  between  you  and  your  principal  point 
of  interest,  the  mountains. 

I  might  illustrate  my  meaning  by  reference  to  Mr.  J.  B.  Bristol's  "  Mount  Equinox." 
(Fig.  184.)  With  half  an  eye  one  can  see  that  if  a  camera  picture  of  this  scene  was 


188 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


brilliant  light  of  the  placid  lake,  with  the  varied  outlines  of  the  gray  mountains 
beyond.     There  is  not  the  atmosphere  that  we  see  in  the  "  Lake  Leman,"  but 


FIG.  184. 


exceptions  to  all  rules.  There 
are  occasions  where  it  is  best 
to  remain  lowly,  but  only  when 
the  best  picture  can  be  so  ob- 
tained. Such  an  instance  is 
exhibited  by  Mr.  Albert  Bier- 
stadt's  magnificent  painting  of 
'•Mountain  Lake."  (Fig.  185.) 
This  is  a  picture  of  a  lake 
hedged  in  among  the  richest 
accessories  of  tree  and  moun- 
tain which  nature  ever  pro- 
vided. Here  are  a  hundred 
pictures  possible  in  one;  but 
it  is  a  picture  of  a  "Moun- 

FIG.  180 


ordered  of  the  photographer, 
he  would  terribly  miss  it  if  he 
attempted  it  from  a  low  point. 
As  it  is  we  have  a  foreground 
full  of  pictorial  value,  a  splen- 
did sense  of  expanse  and  dis- 
tance with  a  charming  view  of 
the  mountains. 

But  to  secure  such  a  combi- 
nation the  artist  must  climb, 
perhaps  two  or  three  inclines 
before  he  can  find  a  proper 
standpoint.  And  yet  there  are 

FIG.  185. 


tain  Lake  "  and  must  not  yield 
to  the  things  which  are  about 
it.  It  will  be  observed,  how- 
ever, that  it  was  not  the  policy 
of  the  artist  to  paint  "the 
whole"  lake  "or  none."  He 
has  chosen  one  of  its  most 
beautiful  curves,  with  a  shore 
line  decorated  by  such  acces- 
sories only  as  are  found  there 
in  nature.  And  after  all  some- 
what of  an  elevation  must  be 
reached  in  order  to  get  just 
such  a  combination. 


OUTDOOR    OPERATIONS. 


189 


there  are  other  qualities  just  as  charming, 
elements  of  beauty  in  one  composition. 

Climbing  comes  good  also 
when  you  have  to  master 
marine  pictures  as  well  as  ' 
those  in  'the  mountains. 
"The  Gull  Rock,"  of  Mr. 
W.  T.  Richards  (Fig.  186) 
shall  be  used  to  help  here.  It 
is  of  one  of  those  occasions 
when,  just  before  the  fog 
pays  its  visit  to  the  shore, 
the  waves,  seemingly  an- 
gered, come  rolling  in  as  if 

FIG.  188. 


Rarely  may  we  hope  to  get  all  the 


FIG.  187. 


to  forewarn,  and  where,  to 
get  the  full  sense  of  the  pic- 
ture your  highest  tripod  or 
the  top  of  a  bath-house 
must  be  used. 

In  the  attempt  to  get  an 
interesting  foreground,  the 
photographer  is  sometimes 
led  to  overdo.  In  other 
words,  crowd  in  too  much. 
I  might  help  you  to  my 
meaning  by  referring  you 
^  to  a  picture  that  is  very 


beautiful,  and  yet,  I  consider, 
faulty  in  the  direction  I  speak 
of.  I  allude  to  Mr.  D.  M.  Arm- 
strong's painting  of  "  The  Har- 
bor Bar,  Mount  Desert."  (Fig. 
187.) 

It  is  true,  this  is  a  "bar," 
and  with  such  accessory  ob- 
jects as  belong  to  a  "bar,"  yet 
it  strikes  me  with  the  feeling 
that  there  are  too  many  objects 
crowded  in,  and  the  effect  of 
the  whole  gives  trouble  to  both 
eye  and  mind  to  puzzle  out  the 
artist's  reason  for  their  intro- 
duction. The  swirl  of  the  lines 


FIG.  189. 


190        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

87.  From  things  terrestrial,  let  us  look  skyward  a  moment  and  take  a  lesson. 

To  obtain  clouds  with  the  landscape  when  there  are  any,  is  often  desirable, 
and  yet,  so  eccentric  are  they  in  form  and  lighting  that  they  do  not  always 
occur  in  harmony  with  the  landscape  in  hand. 

A  good  plan  is  to  devote  a  day  or  more  when  occasion  offers,  to  securing,  some 
negatives  of  clouds  for  the  purpose  of  printing  them  in  the  views  by  the 
process  of  double  printing. 

The  sky,  as  a  rule,  only  requires  as  many  seconds'  exposure,  comparatively, 
as  the  foreground  may  require  minutes;  there  is  little  hope,  ordinarily,  of 

is  also  too  tame.  If  I  had  been  photographing  in  that  locality  I  should  have  chosen  a 
different  combination. 

A  much  more  poetic  feeling  pervades  "  Off  the  North  Head,  Grand  Menan,"  by  Mr. 
A.  T.  Bricher.  (Fig.  188.)  It  is  full  of  lovely  suggestions,  and  would  require  an  elevated 
standpoint  to  secure  its  full  sense  in  a  photograph. 

Of  course,  I  am  only  to  be  understood  as  making  suggestions — as  simply  giving  you  a 
receipt  for  a  developer  but  not  mixing  it  or  not  manipulating  it  for  you.  I  use  the  word 
climb  in  its  literal  sense,  and  its  typical  as  well.  You  must  work  if  you  would  secure 
pictures. 

Even  if  you  stand  on  a  wharf-pile  and  fire  away,  should  you  want  to  get  such  a  pic- 
ture as  "From  a  North  River  Pier,"  by  Mr.  Arthur  Quartley  (Fig.  189),  you  must  climb 
up  to  the  art-rules  and  must  seek  a  place  for  your  camera  where  all  incongruities  and 
inharmonious  objects  will  be  left  out.  I  hope  I  have  not  led  you  too  high. 

P.  S.— Oh !— Don't  forget  about  the  time  of  day.— B.  W.  K. 

87.  The  best  arrangement  for  permitting  the  sky  to  be  secured  in  the  same  negative  as 
the  foreground,  which  I  have  met  with,  is  simply  this  :  I  put,  in  place  of  the  ordinary 
back  to  the  slide^,  a  pane  of  the  red  glass  used  for  operating  windows  set  in  a  narrow  sash 
— a  red  glazed  slide-back,  in  short — and  make  the  focussing-cloth  into  a  hood  at  the  back, 
so  as  to  shut  out  all  outside  light.  I  am  able,  in  this  way,  to  see  the  image  on  the  sensi- 
tized film  with  almost  as  much  distinctness  as  on  the  ground-glass.  I  then,  with  one  of 
the  flap  shatters,  or  a  movable  screen,  the  edge  of  which  is,  if  necessary,  adapted  to  the 
parts  to  be  kept  longest  exposed,  cover  the  sky  and  extreme  distance  over  rapidly,  and 
more  and  more  slowly  ag  the  view  darkens  and  the  foreground  passes  into  shadow.  So 
far  as  the  view  permits  this  simplicity  of  treatment,  the  operator  may  work  with  as  much 
certainty  as  if  he  were  shading  a  print.  If  a  dark  object  comes  up  against  the  sky,  that 
must  be  treated  with  the  closed  foreground  by  a  screen  with  an  aperture  properly  ar- 
ranged, and  can  best  be  done  by  a  subsequent  reopening  of  the  lens  by  the  reverse 
operation,  inclosing  the  foreground  and  the  dark  object  first,  and  not  letting  the  sky  be 
exposed  at  all.  It  is  evident  that  the  range  of  subjects  which  can  be  masked  in  this  way 
is  mainly  limited  to  those  in  which  the  division  of  sky  and  land  is  simple  and  broad ; 
but  in  the  view  exhibited  there  were  slight  irregularities  of  outline  in  the  darker  planes, 
which  were  met  in  this  way  perfectly,  and  the  foreground,  which  was  very  dark  and 
green,  had  more  than  as  many  minutes'  exposure  as  the  sky  had  seconds. 


OUTDOOR    OPERATIONS.  191 

securing  skies  and  clouds  as  well  as  foreground  at  the  same  exposure.  Hence 
the  separate  printing  from  a  sky  negative  becomes,  ordinarily,  necessary.  This 
necessity  under  many  circumstances  is  not  an  evil.  Nature  does  not  select ; 
art  does ;  hence  the  capable  artist  will  select  such  a  sky  for  his  landscape 
as  may  best  complete  his  composition  without  violating  natural  truth.  At 
times,  however,  the  landscape  is  found  with  a  sky  which  yields  the  highest 
pictorial  conditions,  whilst  the  play  of  light  and  shadow  on  the  landscape  is 
inseparable  from  the  sky  above  it.  In  such  a  case  the  landscape  and  sky 
ought  to  be  obtained  at  the  same  time,  even  if  printed  separately.  To  meet 
such  cases,  and  secure,  if  possible,  the  result  in  one  printing,  various  con- 
trivances have  been  devised  to  give  the  sky  a  diminished  exposure :  stops  with 
graduated  aperture,  allowing  less  light  to  reach  the  sky ;  means  of  controlling 
development,  so  as  to  give  little  to  the  sky,  much  to  the  foreground ;  shading 
a  portion  of  the  lens  during  exposure ;  and  shading  a  portion  of  the  plate 

There  is  nothing  new  in  the  use  of  the  screens,  but,  so  far  as  I  have  learned,  no  one 
has  employed  the  red  glass  slide-back  in  this  way  to  direct  the  screening. — W.  J. 
STILLMAN. 

By  a  skilled  hand  artificial  clouds  may  be  made  on  the  negative,  but  this  would  not  at 
all  apply  to  stereo  work. 

The  plan  that  I  have  for  years  adopted — and  in  no  case  has  the  reality  of  the  effects 
produced  been  for  an  instant  doubted — is  as  follows : 

I  first  take,  as  opportunity  offers  (and  with  the  same  lenses  and  camera  used  to  take 
the  views),  a  series  of  cloud  negatives — merely  shadows,  if  I  may  so  express  it — instan- 
taneously, so  that  sky,  and  sky  only,  is  the  result,  letting  the  shadows  of  the  clouds  be 
nearly  transparent,  as  this  saves  much  time  in  the  printing. 

When  about  to  use  these  sky  negatives  (we  will  suppose  that  the  prints,  which  are 
stereoscopic,  have  been  printed),  the  print  should  be  laid  on  a  piece  of  wood,  covered 
with  cloth  (the  back  of  a  printing- frame  will  do),  and  on  this  must  be  placed  the  cloud 
negative,  placing  it  where  it  will  most  harmonize  with  the  view,  and  also  taking  care 
that  it  is  parallel  with  the  lines  in  the  print.  It  is  now  taken  out  in  the  sun,  and  a  piece 
of  card,  which  covers  all  but  the  sky,  is  kept  moving  slowly  from  a  little  above  the 
highest  portions  of  the  view  during  the  exposure,  which,  with  such  a  negative  as  I  have 
described,  would  not  take  more  than  one  or  two  minutes. 

No  fear  need  be  entertained  of  allowing  the  clouds  to  print  a  little  over  the  top  portion 
of  the  picture,  for  this  will  not  show  unless  under  very  extraordinary  conditions,  such  as 
a  white  church  spire  against  the  sky.  A  gradual  lightening  of  the  sky  toward  the 
horizon,  arising  from  the  movement  of  the  card  allowing  less  light  to  fall  on  that  part, 
gives  a  very  artistic  effect,  the  same  as  is  given  in  merely  shading  a  sky,  as  is  often  done. 

Anyone  who  will  try  this  method  will,  I  am  sure,  no  longer  have  chalky  masses  on  the 
upper  part  of  his  pictures  to  represent  a  sky.  Never  mind  if  the  sky  prints  rather  dirty 
to  begin  with ;  the  clouds  will  hide  it. 


192        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

during  exposure.  The  latter  plan  is  manifestly  the  best  when  it  can  be 
satisfactorily  managed. 

With  modern  dry  plates  skies  are  more  readily  obtained,  and  the  latitude 
afforded  in  development  by  them  makes  it  easier  to  secure  landscape  views  with 
clouds  than  it  was  in  the  "  wet "  days. 

88.  The  inclination  of  the  camera,  up  or  down,  is  a  fault  which  the  novice 
is  apt  to  overlook.  In  portraiture  you  may  easily  study  the  effect  of  placing 
the  camera  too  low  or  too  high,  by  observing  the  face  of  friend  or  foe,  as  you 
sit  down  before  him,  stand  face  to  face  with  him,  or,  upon  a  chair,  look  down 
upon  him.  For  portraits,  as  a  rule,  it  is  better  to  work  with  horizontal  or 
nearly  horizontal  apparatus,  and  to  secure  the  want  of  sharpness  of  the  front 
parts  of  a  sitting  figure  by  inclining  the  ground-glass  (swing  back). 

In  landscape  photography  a  horizontal  position  of  the  camera  is  almost  a 
necessity ;  particularly  is  this  the  case  with  architectural  objects.  If  we  neglect 
this  and  give,  for  instance,  an  upward  direction  to  the  apparatus,  we  will  find 
that  the  vertical  lines  converge  toward  the  top. 

A  great  many  pictures  now  in  existence  will  explain  this.  A  landscape 
which  has  no  architectural  objects  in  it  will  show  these  errors  a  great  deal  less, 
and  it  may  often  be  of  advantage  to  raise  the  front  of  the  camera  a  little.  I 

Much  has  been  said  on  the  fact  that  clouds  and  landscape  taken  at  different  times  are 
not  proper  and  cannot  be  artistic.  This,  I  think,  is  not  the  case,  as  with  a  dozen  cloud 
negatives,  taken  under  different  aspects  of  light,  half  the  negatives  ever  taken  might  be 
suited.  They  may  be  printed  from  back  or  front,  to  suit  the  lighting  of  the  view,  and, 
if  more  variety  be  wanting,  may  even  be  turned  upside  down ;  but  this  I  should  hardly 
recommend.— WALTER  B.  WOODBURY. 

Another  plan  is  to  regulate  the  influx  of  light  into  the  camera  by  means  of  a  folding 
•  door  in  front  of  or  within  the  camera.  This  helps  to  remedy  the  evil  only  partially  ; 
besides  this,  it  cuts  off  the  light  too  abruptly,  and  is  apt  to  form  a 
line  or  division  where  greater  intensity  takes  place.  The  method 
which  I  here  present  has  been  tried  very  successfully,  so  much  so 
that  it  becomes  an  earnest  recommendation  to  lens  makers  to 
supply,  with  their  lenses,  a  set  of  diaphragms  that  assist  in  pro- 
ducing this  good  effect. 

Instead  of  having  a  round  aperture  in  each  stop,  let  it  be  of  a 
triangular  shape,  that  is,  a  circumscribed  equilateral  triangle,  with 
the  apex  upward,  as  shown  in  Fig.  190. 

It  is  evident,  from  the  shape  of  the  aperture,  that  the  sky  sends 
through  the  lens  the  smallest  quantity  of  light,  whilst  the  landscape 
transmits  the  most ;  the  increase  of  light,  too,  from  above  downwards,  is  gradual,  thus 
producing  no  harsh  line  between  the  sky  and  the  landscape.— PROF.  J.  TOWLER. 


OUTDOOR    OPERATIONS. 


193 


have  often  done  this  in  taking  an  avenue  of  trees,  and  it  gave  me  a  much  deeper 
view  into  the  foliage. 

Much  liberty  is  gained  by  placing  the  apparatus  above  ground.  Go  to 
the  first,  second,  or  third  story  of  a  house,  or  even  climb  hills  or  mountains, 
that  you  may  overlook  a  larger  area.  Very  high  or  large  and  imposing 
structures  often  appear  so  distorted,  when  taken  from  the  ground,  as  to  render 
them  painful  to  the  aesthetic  eye. 

An  example  in  portraiture  where  the  lens  has  been  too  low,  will  be  found  in 
the  last  chapter,  page  172.  The  notes  below  supply  some  useful  suggestions 
on  this  point. 

89.  This  brings  us  to  the  next  topic  for  discussion,  namely,  perspective. 

Photography — poor,  abused  art — has  always  been  a  most  "  willing  horse  " 
among  its  kindred.  This  has  rather  spoiled  its  votaries,  and  caused  them  to  be 
more  exacting  sometimes  than  is  reasonable.  In  the  matter  of  exposure,  for 
example,  as  I  shall  presently  try  to  show,  the  gourmand  disposition  of  the 
disciples  of  Daguerre  has  led  them  into  quite  a  hole  of  error. 

So  is  it  in  the  direction  of  the  amount  of  subject  it  is  proper  to  desire  in  a 

89.  If  we  take  a  photograph  of  a  cube  one  foot  high,  and  place  the  objective  on  a  level 
with  the  cube,  the  edges  will  separate  but  little,  and  the  cube  will  look  as  represented 
in  Fig.  191.  If,  on  the  other  hand,  we  photograph  a  cubical  building  which  is  sixty 
feet  high,  and  place  the  camera  at  the  foot  of  the  building,  then  the  lines  of  the  cornices, 
a  e  and  a  c,  will  "  tumble  "  very  considerably,  as  the  artists  call  it ;  and  the  higher  the 
building  is,  the  more  marked  will  this  appear. 

I  once  saw  a  photograph  of  a  monument  which  appeared  exactly  as  Fig.  191.  The 
lines  of  the  cornice  did  not  fall  sufficiently,  and  did  not  give  the  same  impression  that 
high  structures  would  make. 

The  question  arises,  could  this  be  avoided  ?  At  first  sight  this  seems  impossible.  And 
still  it  can  be  done.  If  we  photograph  a  cube,  and  place  the  objective  at  various  distances 


FIG.  191. 


FIG.  192. 


from  the  camera,  we  will  find  that  the  lines  tumble  more  and  more  the  closer  we  get  to 
the  cube.  When  we  get  very  close,  and  the  objective  is  on  a  level  with  the  base  of  the 
model,  we  will  obtain  a  picture  like  Fig.  192.  Such  an  approach  is  possible  with  a  correct- 

13 


194 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  193. 


view.  If  a  wide-angle  lens,  the  focal  length  of  which  is  less  than  eight  or  ten 
inches,  is  employed,  the  distance  is  distorted — near  objects  are  enlarged  and 
distant  ones  brought  too  close  in  appearance.  Let  me  illustrate.  Cut  a  hollow 

rubber  ball  in  two, 
and  turn  the  hol- 
low side  of  one-half 
toward  you.  It  pre- 
sents the  half  of 
a  globe — a  hemi- 
sphere. Carefully 
seize  the  sides  and 
pull.  You  thus 
destroy  the  spheri- 
cal form  and  bring 
the  extreme  inner 

surface  nearer  to  you.  So  acts  the  lens,  when  one  of  too  short  focal  length  is 
used.  Painters  have  more  liberty  in  this  direction.  For  example,  in  a  pic- 
ture like  "An  August  Morning,"  by  Mr.  E.  Swain  Gifford  (Fig.  193),  there 

working  wide-angle  lens,  as,  for  instance,  the  Zentmayer.  Such  lenses  have  sufficient 
depth,  and  make  it  possible  to  work  at  very  short  distances. — DR.  H.  VOGEL. 

To  obtain  a  correct  small  picture  of  an  object,  the  reduction  in  size  must  not  be  accom- 
plished by  using  a  short  focus  lens,  but  by  taking  one  of  a  proper  focal  length  to  a 
distance  such  that  the  object  is  thereby  reduced  to  the  size  desired;  unless  intervening 
objects  render  such  a  course  impossible.  I  mean  that  if  we  want  a  picture  of  three 
inches  by  four  of  an  object,  we  shall  not  do  well  to  use  a  lens  that  gives  images  of  that 
size,  but  we  should  take  a  lens  of  longer  focus,  say  an  eight-inch  lens,  and  go  to  a  dis- 
tance such  that  the  object  is  brought  into  the  required  limits.  With  natural  scenery 
very  pretty  pictures  are  often  obtained  by  these  short-focus  lenses.  But  they  are  incorrect 
representations;  the  only  difference  is  that  the  eye  cannot  detect,  as  in  the  case  of 
architecture,  the  faults  that  have  been  introduced,  unless  previously  familiar  with  the 
scene  depicted. 

It  is  not  improbable  that  some  of  my  readers  may  doubt  the  fact  that  I  have  here  so 
positively  affirmed  of  the  equality  of  the  perspective  angles  produced  by  different  lenses 
of  different  focal  lengths  when  taken  from  the  same  station-point.  It  is  common  to  speak 
of  the  sharp  angles  produced  by  lenses  of  short  focal  lengths,  and  those  views  which  we 
are  accustomed  to  see  produced  by  short  focus  lenses  are  habitually  taken  from  station- 
points  too  near  the  object.  So  that  two  causes  concur  to  make  these  sharp  angles  painful, 
first,  that  they  are  rendered  additionally  sharp  by  being  taken  from  too  short  distances, 
and  second,  that  short  focus  lenses  produce  small  pictures  in  which,  as  above  explained, 
the  eye  refuses  to  tolerate  sharp  angles. — M.  CAREY  LEA,  M.D. 


OUTDOOR    OPERATIONS. 


195 


Fio.  104. 


is  an  amount  of  subject  which  it  would  be  impossible  to  secure  iu  a  pho- 
tograph from  the  same  point  of  sight,  and  at  the  same  time  preserve  proper 
perspective. 

When  proper  distance 
can  be  had  and  the  cor- 
rect elevation  for  the 
camera  secured,  as  illus- 
trated by  the  fine  view  of 
"  Harbor  Islands,  Lake 
George,"  by  Mr.  H.  W. 
Robbins(Fig.l94),  then 
we  can  obtain  quantity 
of  subject  and  quality, 
though,  of  course,  the 
objects  must  be  dimin- 
ished. 

Fl»-  195.  .  90.  As  you  see,  in  pho- 

tography one  quality  or 
element  of  beauty  is  se- 
cured usually  at  the  ex- 
pense of  another.  We 
may  only  hope  for  meas- 
ured success  by  carefully 
averaging.  This  is  true, 
no  matter  whether  we  are 
photographing  by  the  sea- 
side, among  the  lakes  and 
mountains,  "On  the  Des- 
ert" with  Mr.  Frank  Waller  (Fig.  195),  where  the  camels  and  the  Bedouin 
combine  with  the  dead  wadies  and  the  fertile  oasis  to  make  us  picturesque 

90.  Supposing  that  two  lenses  of  different  focal  lengths  are  so  placed  that  a  given 
dimension  is  equal  in  the  two  pictures,  what  law  will  govern  the  size  which  any  other 
dimension  will  have  in  each? 

Let  us  suppose  that  a  poplar  tree  stands  in  the  centre  of  the  picture,  that  is,  directly 
before  the  eye,  and  that  another  of  equal  height  stands  to  the  right,  and  further  back ; 
for  simplicity  let  us  say  that  it  is  as  much  further  back  as  it  is  to  the  right.  The  line 
joining  the  two  will  then  make  an  angle  of  forty-five  degrees  with  the  line  of  sight,  that 


196 


WILSON'S    QUARTEK    CENTUKY    IN    PHOTOGRAPHY. 


FIG.  196. 


subjects,  or  in  view  of  the  "  Cedars  of  New  England  "  with  Mr.  R.  Swain  Giiford 

(Fig.  196),  whose  brush  has 
given  us  so  many  admirable 
lessons  in  composition  and 
color. 

The  work  of  the  painter 
and  that  of  the  photogra- 
pher are  largely  akin  where 
the  principles  of  art  are 
involved,  only  the  photog- 
rapher is  expected  to  tell  the 
truth,  while  the  painter  is 
not  so  apt  to  be  questioned. 

is,  in  Fig.  197,  A  M  is  equal  to  A'  M.    Also,  FIG.  197. 

we  can  simplify  the  figure  and  construction 
by  supposing  that  the  base  of  each  tree  is  on 
a  level  with  the  eye. 

The  tree  A  B  has,  by  condition,  the  same 
height  as  A/  B',  but  the  latter  being  farther 
•will  be  represented  smaller  in  a  perspective 
drawing,  and  the  amount  of  this  reduction 
is  wholly  dependent  upon  the  focal  length  of  the 
lens. 

Let  us  take  AF  to  represent  the  focal 
length  of  any  lens.  Then  determine  the 
vanishing-point  of  the  line  connecting  the 
two  trees  by  drawing  F  V  parallel  to  A  A/) 
the  intersection  of  F  V  with  the  line  A  V, 
perpendicular  to  the  line  of  sight  F'  A,  viz.: 
V  will  be  the  vanishing-point.  Draw  the 
line  B  V,  and  connect  F  with  A'.  At  the 
point  C  where  this  last  line  cuts  A  Ferect  a 
perpendicular  till  it  intersects  FB'.  The 
length,  CD,  of  this  perpendicular  will  be  the 
comparative  height  which  the  distant  tree 
will  have,  as  depicted  by  the  short  focus  lens, 
the  nearer  tree  having  the  fixed  height,  A  B. 

Let  us  take  A  F'  to  represent  the  focal 
length  of  a  lens  of  twice  the  focus  of  the 
preceding.     The  new  vanishing-point  V  is 
determined  in  the  same  manner  as  before.     Connect  JF*  with  the  top  and  base  of  A/  B' 
and  in  the  same  way  as  before  determine  the  height,  Gffof  the  tree. 


OUTDOOR    OPERATIONS, 


197 


Photography  has  had  to  bear  a  great  deal  of  unjust  criticism,  simply  because 
critics  are  ignorant  of  what  it  means  to  produce  a  photograph — what  is  in- 

We  see,  then,  that  the  two  lenses  being  so  regulated  in  distance  that  both  give  the 
nearer  tree  the  same  height,  A  B,  the  more  distant  tree  is  reduced  in  height  by  the 
shorter  focus  lens  to  CD,  whereas  the  longer  focus  reduces  it  only  to  G  H. 

The  diiference  of  these  two  heights  is  very  striking.  But  this  is  not  all ;  everything 
else,  as  I  before  remarked,  is  changed.  The  lateral  distance,  M A/,  in  actual  dimension, 
is  reduced  by  the  long  focus  lens  to  A  G ;  by  the  short  focus,  still  more,  and  is  brought 
in  to  C.  The  perspective  angle  of  a  line  joining  the  summits,  is  also  altered.  Suppose 
the  lines  A  B,  A/  B/,  represented,  not  trees,  but  the  nearer  and  farther  end  of  a  building, 
of  which  B  B'  was  the  eave,  the  perspective  angle  would,  in  the  one  case,  "be  A  B  D,  in 
the  other  A  B  H. 

The  relative  distance  from  the  front  is  affected  in  the  same  way,  but  in  Fig.  197  this  is 
concealed  in  consequence  of  the  assumption  which  we  made  that  the  bases  of  both  trees 
were  on  the  level  of  the  eye,  i.  e.,  the  horizontal 

line  A  V,  which  was    done  to  simplify  the  FIG.  198. 

figure.  To  show  this  further  point,  let  us  sup- 
pose the  level  of  the  eye  to  correspond  with  the 
middle  of  the  height  of  each  tree,  then  the  effect 
of  the  two  focal  lengths  upon  the  image  will  be 
exhibited  by  Fig.  198,  in  which  the  vanishing- 
points  are  omitted. 

Here  it  will  be  seen  that  the  short  focus  lens 
not  only  diminishes  the  size  of  the  farther  tree 
much  more  than  does  the  longer,  but  it  brings 
it  nearer  laterally  to  the  line  of  vision,  and 
throws  it  farther  back.  On  the  contrary,  the 
longer  focus  lens  draws  the  distant  tree  further 
forward  and  further  outward,  and  increases  its 
apparent  height :  effects  that  all  photographers 
see  constantly  taking  place  within  their  own 
experience. 

And  if  we  imagine  that  A  B,  A'  B',  represent, 
not  trees,  but  the  nearer  and  farther  end  of  a 
building  seen  obliquely,  then  the  lines  A  B  CD 
will  represent  the  side  of  that  building  as  it  will 
will  be  reproduced  by  the  shorter  focus  lens; 
A  G  HB  as  by  the  longer,  producing  the  same 
comparative  effect  as  shown  in  Fig.  197  of  the 
first  part.  If  the  lines  A  C,  B  D  (Fig.  198),  were 
extended,  they  would  give  the  vanishing-point, 
and  so  with  A  G,  B  H. 

An  objection  may  be  made  by  some  readers  that  the  height  of  the  tree?,  A  B,  A/  B',  is 


198 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


volved  in  making  a  photographic  picture.  A  person  who  attempts  art  should 
be  well  versed  not  only  in  the  principles  of  art,  but  should  thoroughly  under- 
stand the  technique.  And  so  should  the  photographic  critic  not  only  under- 

not  represented  upon  the  same  scale  in  the  figure,  as  the  focal  lengths.  To  explain  this, 
it  becomes  necessary  to  say  a  word  on  apparent  magnitudes. 

Suppose  we  are  working  with  a  lens  of  6-inch  focal  length,  and  that  the  tree  is  75  feet 
from  the  lens.  This  ratio  of  75  :  £,  or  150  : 1,  represents  the  scale  on  which  the  tree  will 
be  depicted  on  the  ground-glass.  If  the  tree  be  50  feet  high,  then  its  height  in  the 
picture  will  be  f&  feet,  or  4  inches.  Now,  if,  in  Fig.  197,  A  ^represents  the  focal  length 
of  the  lens,  to  with,  6  inches,  A  B  may  be  taken  as  representing  the  correct  height  of  the 
tree,  or  f  as  much. 

The  same  reasoning  will  enable  us  to  determine  in  every  case  what  size  an  object  of  a 
given  height  and  distance  will  have  on  the  ground  glass  with  any  lens.  It  must  be 

rigorously  borne  in  mind,  however,  that  the  tree  or 
object  is  here  supposed  to  be  exactly  on  the  central 
line  F'  M.  If  it  is  not,  we  must  take  as  the  basis  of 
our  scale,  not  the  other  oblique  distance,  measured 
from  the  eye  to  the  tree,  but  from  the  eye  to  a  point 
on  the  central  line  opposite. 

Suppose  we  place  a  lens  of  12-inch  focus  at  E,  and 
have  at  A  a  tree  200  feet  off  and  50  feet  high,  this  tree 
will  be  depicted  on  the  ground-glass  -£fo  of  one  foot 
or  3  inches  high — that  is  its  height  divided  by  its  dis- 
tance A  E.  Suppose  another  tree  of  equal  height  at 
C,  the  line  A  C  making  an  angle  of  45  degrees  with 
A  B,  what  will  be  its  height? 

Here  we  must  not  divide  its  height  by  its  distance 
E  (7,  unless  we  intend  to  turn  the  camera  round  so  as  to 
bring  it  to  the  centre  of  the  picture.  If  the  camera  re- 
mains pointed  in  the  direction  EA,  we  must  consider 
EB  as  the  effective  distance  of  the  object.  If  we 
suppose  A  B  to  be  half  of  AE,  or  100  feet,  then  the 
size  of  the  farther  tree  upon  the  ground-glass  will  be  ^50°j  feet,  or  2  inches.  In  this  case, 
the  relative  height  of  the  two  trees  is  as  3  to  2.  It  may  not  be  uninteresting  to  observe 
how  this  proportion  will  stand,  supposing  that  we  substitute  a  lens  of  half  the  focal 
length  of  the  former,  and  bring  up  the  size  of  the  image  of  the  nearer  tree  to  3  inches, 
by  moving  the  lens  to  F,  one-half  the  distance  from  it. 

The  nearer  tree  is  now  but  100  feet  off,  but  our  unit  being  reduced  from  1  to  £,  the 
scale  will  therefore  be  ^^,  the  height  of  the  first  tree  ^50°jj,  or  3  inches,  as  before.  The 
second  tree  is  now  200  feet  off,  its  scale  will  be  ¥J7,  and  its  height  -ffo,  or  lj  inches. 
The  perspective  heights  of  the  two  trees,  therefore,  as  given  by  the  smaller  lens,  in  place 
of  being  as  3  to  2  as  in  the  case  of  the  larger  focus  lens,  will  be  as  2  to  1.  These  results 
agree  approximately  with  those  given  in  Fig.  197,  although  that  figure  was  not  drawn 
for  such  a  purpose  ;  it  still,  however,  illustrates  pretty  well  these  measurements. 


OUTDOOR    OPERATIONS.  199 

stand  the  principles  of  art  but  the  photographer's  methods  of  producing  the 
technical  excellences  of  his  work  should  also  be  understood.  Otherwise  the 
critic  can  have  no  "  feeling "  for  his  work,  and  without  feeling  one  may  as  well 
get  "out  of  focus" — diffuse — at  once. 

And,  finally,  since  outdoor  operations  give  the  camera  worker  a  wider  field, 
so  do  they  give  him  larger  opportunities  for  the4  exercise  of  art  information. 
Faces  may  be  lovely  and  beautiful,  but  to  work  amid  the  loveliness  and  beauty 
of  nature,  is  a  privilege  above  all  which  photography  affords.  Let  it  be  meas- 
ured from  a  lofty  standpoint  and  treated  accordingly. 

Briefly,  then,  we  conclude  that  all  lenses  (setting  aside  such  imperfections  as  belong 
to  their  construction)  will,  when  placed  at  the  station-point,  give  pictures  varying  only 
in  scale.  But  that  when  the  same  scene  is  taken  from  two  different  station-points, 
everything  is  changed.  If  we  increased  our  distance  from  any  given  object  in  the 
picture,  to  double  or  treble,  and  yet  keep  that  object  of  the  same  size  in  the  image,  by 
using  a  lens  of  double  or  treble  the  focal  length,  as  the  case  may  be,  though  that  one 
object  may  remain  unchanged,  everything  else  will  be.  Also,  that  short  focus  lenses 
cannot  give  correct  results,  which,  in  small  pictures,  are  only  to  be  obtained  by  using 
lenses  of  sufficient  focus,  and  retaining  the  central  portion  of  the  picture  corresponding 
to  the  size  required. — M.  CAREY  LEA,  M.D. 

I  usually  carry  four  pairs  of  lenses,  varying  from  2J  to  10  inch  focus,  for  stereoscopic 
work,  and  a  10  inch  Morrison  for  single  views,  each  fastened  on  its  separate  front,  fitted 
to  my  camera,  and  all  contained  in  a  light  wooden  box  with  space  for  each.  This  box 
I  carry  in  my  hand  to  each  point  of  view,  and  select  lenses  to  suit  the  subject,  invariably 
choosing  the  longest-focussed  instrument  that  can  be  used  in  the  prescribed  limits,  as 
wide  angles  fill  the  foreground  with  unimportant  objects,  and  dwarf  stately  mountains 
down  to  insignificant  lines. 

For  landscapes,  I  prefer  single  (achromatic)  lenses,  as  the  slight  curvature  at  the 
margin  is  ordinarily  of  no  account,  and  more  than  compensated  for  by  the  greater  sharp- 
ness and  detail  obtained.  They  are  also  (when  perfectly  clean)  free  from  a  trouble  which 
sometimes  goes  with  the  very  best  of  combination  lenses,  a  centralization  of  light,  and  a 
fuzziness  at  the  edges  where  a  dark  object  is  brought  against  a  strong  light.  Some  of 
my  best  work  has  been  produced  with  a  pair  of  object-glasses  taken  from  an  ordinary 
opera  glass  (3  inch  focus),  mounted  in  rigid  settings,  and  properly  diaphragmed  in  front. 

For  architectural  work,  something  better  is  needed,  and  found,  in  the  "  Morrison  "  and 
"  Dallmeyer  "  wide-angle,  rectilinear  lenses,  which  take  in  an  angle  of  nearly  a  hundred 
degrees ;  they  are  expensive  but  invaluable  and  perfect  in  their  way ;  in  my  mind  there 
is  little  choice  between  them,  and  an  outfit  would  be  incomplete  without  a  pair  of  either 
one  kind  or  the  other,  2£  inch  focus  for  confined  situations,  interiors,  or  mountain  gorges 
and  waterfalls,  such  as  I  have  often  found  among  the  Adirondacks.  Of  course,  the  rule 
requiring  as  long  a  focussed  instrument  as  possible,  holds  good  and  applies  with  even 
greater  force  to  architectural  subjects,  but  this  smaller  kind  of  lens  is  often  necessary  for 
field  work  simply  because  a  single  lens  cannot  be  found  of  sufficiently  wide  angle. — 
S.  E.  STODDARD. 


200 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  200. 


91.  Next  to  clouds,  the  most  unreliable  objects  which  can  be  imagined  to 
test  the  patience  of  the  photographer  are  living  animals.     I  need  not  speak  of 

the  number  of  their  legs. 
Sometimes  the  fewer  the 
legs  the  more  the  trouble. 
But  it  will  console  tried  and 
tested  operators  to  know 
that  art  principles  will 
here  also  come  to  the  rescue. 
Even  a  "  Group  of  Sheep  " 
may,  as  we  see  by  a  draw- 
ing from  Mr.  T.  Robin- 
son's lovely  picture  (Fig. 
200),  be  treated  so  that  the 
masses  of  light  and  shade 
and  the  arrangement  of 
the  figures  shall  comply 
strictly  with  the  rules  of 
art.  And  so,  Mr.  J.  Wells 
Champney,  in  "The  Arrival  of  the  Stage"  (Fig.  201),  has  so  grouped  and  lighted 

91.  It  is  only  of  late  years  that  artists  even  are  growing  to  appreciate  fully,  in  this 
country,  the  beauty  of  picturesque  figures  in  many  subjects.  Partly  from  the  character 
of  our  grand  wild  scenery  which  has  formed  the  field  of  study  for  our  landscape  painters, 
and  does  not  require  the  addition  of  human  life,  being,  indeed,  often  better  without  it, 
and  partly  from  a  want  of  training  of  landscape  painters  in  the  figure  branch  of  the  art, 
those  interesting  rural  home  bits  which  are  so  much  enhanced  by  suitable  figures  and 
domestic  animals,  have  been  to  a  great  extent  neglected,  and  I  think  with  loss  to  the  art 
of  the  country,  because  works  of  this  class,  while  they  illustrate  so  much  that  is  interes- 
ting and  dear  to  us,  and  full  of  poetic  sentiment  of  home,  are  capable  of  showing  the 
highest  degree  of  talent  and  skill  in  all  the  best  art  qualities. 

Much  more  is  attainable  in  landscape  photography  in  the  way  of  small  rural  scenes 
than  in  grand  extended  landscape.  And  one  reason,  in  addition  to  such  bits  that  com- 
pose well  being  infinitely  more  numerous  than  scenes  more  extended,  is  that  the  principal 
objects  are  all  near,  and  consequently  admit  of  the  finished  rendering  of  those  exquisite 
details  which  constitute  one  of  the  principal  beauties  of  photographs.  But  such  rural 
bits  are  almost  invariably  greatly  enhanced  in  their  interest  and  beauty  by  suitable 
groups  of  figures.  And  here  exists  one  of  the  greatest  difficulties  that  the  earnest  worker 
after  agreeable  pictures,  got  with  the  camera,  has  to  contend  with,  for  while,  as  I  say, 
there  is  nothing  which  so  enhances  the  completeness  of  such  pictures,  there  is,  on  the 
other  hand,  nothing  which  so  completely  mars,  I  may  even  say  destroys  a  picture  as 


OUTDOOR    OPERATIONS. 


201 


FIG.  201. 


his  figures  as  to  secure  a  very  charming  and  natural  effect.  Every  one  seems 
to  be  doing  something,  all  with  a  unity  of  purpose,  which  is  delightful.  Not 
a  soul  there  who  is  not 
employed  in  some  way  in 
the  consideration  of  the 
"arrival"  of  that  stage 
There,  see,  the  pleasant 
greeting,  the  helping  hand, 
the  busied  baggage  handler, 
the  interested  old  man  in 
the  chair,  the  children  rest- 
ing from  play  while  they 
look  on — all,  all  helping  to 
tell  the  story  in  the  most 
natural  way,  and  yet  all 
composed  in  the  most  ar- 
tistic way.  Ten  years  ago 
a  photographer,  when  attempting  to  picture  an  "arrival,"  would  pose  every 
available  person  at  the  rear  of  the  stage,  in  a  line,  all  looking  in  the  camera, 

figures  which  are  ill  adapted  to  it,  or  badly  placed,  or  unsuitably  clad,  or  awkwardly 
posed,  Even  the  getting  them  of  a  proper  size  in  a  photograph  is  a  very  difficult  matter 
always.  If  retired  to  such  distance  that  they  become  buried  in  insignificance,  of  course 
they  are  useless,  and  the  nearer  we  approach  them,  not  only  from  their  increased  size, 
but  from  the  inevitable  distortion  caused  by  the  lens,  the  greater  become  our  difficulties. 
When  groups  of  figures  attain  so  much  importance  as  to  balance  equally  the  attention 
with  the  landscape,  the  effect  is  not  apt  to  be  good,  one  or  the  other  must  be  subordinated, 
and  in  the  character  of  work  of  which  I  am  now  writing,  the  figure  groups,  while  they 
play  an  important  part 'in  the  picture,  should  at  the  same  time  be  entirely  subordinate  to 
their  surroundings.  It  is  a  difficult  matter  to  manage  a  single  figure,  especially  a  man; 
standing  he  is  like  a  post,  and  sitting  he  is  an  unpleasant  conglomeration  of  angles. 
The  drapery  in  the  skirts  of  women  and  girls,  and  their  more  varied  hues  of  attire,  are  a 
great  assistance.  Two  figures  are  better  than  one,  and  three  still  better.  Occasionally  a 
group  of  a  half  a  dozen  will  come  in,  but  rarely.  The  more  you  have  the  greater  become 
your  difficulties  in  posing  them.  A  grown,  or  nearly  grown  person  and  one  or  two  chil- 
dren make  a  picturesque  combination,  and  they  should  be  clad  in  such  garments  that 
those  on  the  upper  portion  of  the  figure  be  in  light  and  the  lower  in  dark  mass,  or  vice 
versa.  This  will  enable  the  getting  of  the  light  portion  of  the  figure  relieved  from  a  dark 
shadow  back  of  it,  or  the  dark  from  a  light  backing,  which  adds  greatly  to  the  relief  and 
picturesqueness.  A  person  clad  in  gray,  or  black,  or  white  from  head  to  foot  is  abso- 
lutely useless  to  introduce  into  a  picture,  for  in  coming  against  a  varied  background  one 


202 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


each  eyelash  sharp — before  exposing  his  plates.     The  camera  can  do  just  as 
well,  now,  as  the  brush  can. 

92.  Now  if  the  subject  is  a  wide-angled  one,  such  as  conies  to  us  in  a  "  New 
England  School/1  by  Mr.  A.  F.  Bellows  (Fig.  202),  we  find  a  great  deal  of 


FIG.  202. 


life  is  added  to  the  picture  by  the  introduction  of  the  figures.  Without  them 
we  would  obtain  a  fine  landscape,  but  the  sense  of  quiet  would  so  pervade  the 
whole  as  to  render  us  sceptical — all  jokes  aside — as  to  whether  that  could 
really  be  a  New  England  school.  The  harmony  of  things  must  always  be 
considered  first. 

93.  One  more  allusion  to  the  subject  of  illumination  and  this  lesson  must 
end.  From  a  want  of  knowledge  of  the  principles  of  art  a  morbid  admiration 

half  or  the  other  is  sure  to  be  absorbed  in  its  backing,  and  you  have  only  half  of  your 
figure,  or  if  in  entire  relief  against  an  opposite  ground,  from  head  to  foot,  you  have  a  cut- 
out patch  which  is  dry  and  hard. 

A  very  difficult  matter  is  the  posing.  Even  with  figures  in  repose  there  should  be  a 
certain  kind  of  action,  I  mean  a  reversing  of  the  direction  of  the  upper  and  lower  portions, 
and  of  the  limbs.  This  may  be  carried  to  a  much  greater  extent  in  figures  in  landscapes 
without  an  appearance  of  affectation  than  it  can  in  figure  subjects. — XANTHUS  SMITH. 

93.  We  will  now  take  a  picture  that  has  been  really  produced  by  photography,  and 
see  how  it  was  conceived  and  finished.  To  analyze  and  dissect  a  picture  in  a  cold- 


OUTDOOR    OPERATIONS. 


203 


and  reverence  for  unnaturally  minute  definition  tends  to  lead  the  operator  away 
from  what  should  really  be  the  end  and  aim  of  his  study.  Instead  of  "  going 
in"  for  the  broad,  vigorous  effects  of  light  and  shade  in  the  landscape,  he  is  led 
to  look  upon  a  "mechanical,  organ-grinding"  kind  of  exposure  consequent 

blooded  way,  as  I  am  going  to  do  now,  is  to  rob  that  picture  of  any  poetry  it  may  contain, 
and  leave  nothing  but  a  mechanical  interest,  but  I  know  of  no  better  means  of  convey- 
ing the  information ;  I  will  therefore  take  one  of  my  own — that  one  I  have  called  "  A 
Merry  Tale "  will  be  suitable 
for  the  purpose.     I  have  made 
an  ink-process  reduction  of  the 
picture  (Fig.  203),  which  will 
assist  the  student   in  under- 
standing what  follows. 

In  the  drawing-room  of  a 
country  house  in  North  Wales 
five  young  ladies  in  evening 
costume  were  amusing  them- 
selves after  dinner.  One  of 
them  was  relating  some  funny 
circumstance  to  the  others, 
who  arranged  themselves  in  a 
picturesque  group  round  the 
story-teller.  Here  was  the 
germ  of  the  picture.  A  few 
seconds  sufficed  to  make  a  sketch  of  the  composition.  The  illustration  is  a  reproduction 
of  the  jotting  in  my  note-book,  and  I  may  remark,  by  the  way,  that  the  practice  of 
making  rough  sketches  of  composition  and  light  and  shade  is  very  useful,  especially  if 
accompanied  by  a  few  descriptive  notes.  It  teaches  the  student  how  to  observe,  if  it 
does  no  other  good.  Correct  drawing  is  by  no  means  necessary ;  the  "  effect "  is  what 
should  be  noted.  To  return  to  the  picture.  By  an  easy  transition  the  mind  easily 
changed  the  young  ladies  into  peasant  girls  and  suggested  suitable  surroundings.  A 
sketch  was  made  of  the  arrangement,  and  the  dress  for  each  figure  decided  on.  In 
selecting  the  costumes,  the  light  and  shade  of  the  group,  and  its  relation  to  the  landscape, 
were  not  forgotten,  neither  were  the  accessories — the  basket,  jug,  arid  stick.  The  colors 
were  taken  into  account  only  as  to  how  they  would  translate  into  black  and  white. 

It  was  arranged  that  the  group  should  form  part  of  our  work  for  the  next  day.  Arrived 
at  the  selected  spot,  the  camera  was  unpacked,  and  the  models  placed  approximately  in 
the  proper  places,  interfering  branches  cut  away,  and  everything  got  ready,  so  that  the  last 
moments  might  be  devoted  to  the  quiet  final  touches,  expressions,  and  other  little  things. 

Now  for  the  arrangement  of  the  group.  The  girl  to  the  left  was  sitting  up  at  first,  as 
will  be  seen  in  the  sketch,  but  being  a  young  hand  at  the  business,  she  could  not  control 
herself,  and,  enjoying  the  fun,  threw  herself  back  on  the  bank  screaming  with  laughter. 
This  was  a  happy  accident,  which  much  improved  the  composition,  and  was  seized 


204        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

upon  absurdly  reduced  aperture  as  the  correct  thing,  whilst  to  the  eye  of  the 
artist  the  much  vaunted  result  appears  like  a  landscape  carefully  black-leaded, 
and  then  executed  in  minute  needlework,  qualities  which  are  no  compensation 
for  the  effects  named,  which  have  been  given  by  the  lens  .when  skilfully 
applied  to  this  class  of  subject.  • 

immediately.  She  was  at  once  shouted  to,  to  keep  her  place,  which,  being  an  easy  one> 
required  little  further  thought  on  the  part  of  the  photographer,  who  could  now  turn  his 
attention  to  the  other  figures.  The  seated  figure,  the  one  in  the  straw  hat,  was  a  steady 
old  stager,  with  plenty  of  experience  and  no  nerves ;  she  required  but  a  moment's  atten- 
tion. The  next  figure,  always  dramatic  in  pose,  and  with  a  charming  expression,  is, 
perhaps  in  consequence  of  other  good  qualities,  rather  shaky  as  a  sitter.  She  required  a 
rest  of  some  kind.  The  stick  was  useful  here,  and  was  of  immense  value  in  the  composi- 
tion. A  bit  of  straight  line  to  contrast  a  number  of  curves  is  always  effective.  This 
settled  the  three  figures  that  were  easiest  to  keep  still.  The  standing  pose  being  by  far 
the  most  difficult  to  keep — for  a  standing  figure  without  a  rest  often  sways  like  a  pen- 
dulum— was  left  until  last.  The  figure  telling  the  story  was  now  settled ;  the  pose  came 
easy,  the  model  being  an  admirable  story-teller,  and  thoroughly  up  to  her  business,  but 
it  was  necessary  to  give  all  possible  effect  to  the  hand,  for  the  hand,  if  well  placed,  would 
do  more  toward  showing  the  intention  of  the  picture  than  anything  else  in  it.  It,  in  a 
way,  leads  the  chorus  of  expressions.  It  emphasizes  the  situation — it  makes  you  feel  the 
girl  is  speaking.  It  was  so  arranged  that,  to  make  it  more  conspicuous,  it  should  appear 
partly  in  sunlight  and  partly  in  shadow,  and  every  leaf  or  twig  that  came  behind  it  was 
hurriedly  removed.  The  standing  figure,  who  could  not  be  expected  to  keep  the  pose 
for  above  a  minute  or  two,  was  placed  last.  The  jug,  basket,  and  fox-gloves,  which  form 
the  keynote  of  the  composition  in  the  foreground,  had  been  previously  arranged,  and  all 
was  ready.  But  a  last  glance  from  the  camera  showed  the  photographer  that  the  tree 
was  exactly  over  the  head  of  the  standing  figure,  and  cut  the  composition  into  two  parts. 
This  would  never  do.  But  instead  of  moving  the  model  the  camera  was  moved.  This 
corrected  the  error  to  some  extent.  It  would  have  been  better  to  move  it  a  little 
further,  but  it  was  feared  the  other  tree  would  interfere  with  the  story-teller.  A  few  last 
words — at  the  special  request  of  the  models  I  use  fictitious  names — "  Now,  girls,  let  this 
be  our  best  picture.  Mabel,  scream ;  Edith,  a  steady  interest  in  it  only  for  you ;  Flo, 
your  happiest  laugh ;  Mary,  be  sure  you  don't  move  your  hand,  or  all  the  good  expres- 
sions will  go  for  nothing ;  Bee,  I  will  say  nothing  to  you,  but  leave  you  to  your  fate. 
Steady  !  Done  I "  and  two  seconds'  exposure  settled  the  matter.  I  scarcely  expected  a 
successful  result,  the  thing  was  so  difficult ;  but  as  the  wind  was  blowing  almost  a  gale, 
I  did  not  tare  to  try  another  plate.  As  it  happened,  I  found,  when  I  developed  the  plate 
a  fortnight  afterward,  I  had  got  a  good  negative.  The  sky  was  white  and  blank,  but  the 
use  of  a  second  negative,  delicate  and  not  too  obtrusively  printed,  soon  put  this  matter 
to  rights. 

This  seems  a  long  story  to  tell,  but  the  picture  was  exposed  in  under  six  minutes  from 
the  time  the  models  first  took  their  places.  The  quickness  is  one  of  the  secrets  of  success, 
but  when  your  picture  is  to  include  figures  it  should  not  have  the  appearance  of  hurry, 


OUTDOOR    OPERATIONS. 


205 


FIG.  204. 


The  student  should  note  distinctly,  that  however  astonishing  and  captivating 
good  definition  or  detail  may  be  in  studies  of  foreground,  etc.,  in  the  general 
landscape  fine,  broad  effects  of  light  and  shade  will  supersede  it  all.  Mere 
clean  mechanism  on  the  plate  grows  monotonous,  and  will  always  succumb 
to  the  sentiment  conveyed  to  the  mind  of  the  spectator  by  representations 

for  "  hurry  hinders  haste,"  and,  besides,  has  the  effect  of  flurrying  your  models ;  it  should 
be  the  result  of  a  perfect  knowledge  of  what  you  want  to  do.  A  model  should  never  be 
kept  waiting  longer  than  is  absolutely  necessary.  It  is  better  to  give  up  little  things 
rather  than  to  lose  a  fine  effect. — H.  P.  ROBINSON,  in  Picture  Making  by  Photography. 

One  of  the  first  things  to  look  at,  of  course,  is  to  invent  the  story  you  want  to  tell.  It 
should  always  be  something  that  will  touch  the  feelings  of  all  classes,  if  possible,  or,  as 
Lord  Bacon  has  said,  "come  home  to  the  business  and  bosoms  of  most  men."  In  doing 
so  the  mind,  as  much  as  the  eye,  came  into  play.  Let  me  illustrate  by  a  picture  that  it 
is  possible  to  imitate  wherever  harvest  fields  grow.  It  is  called  "  The  Harvesters  at 
Rest,"  by  Mr.  Wyatt  Eaton  (Fig.  204),  one  of  the  choicest  compositions  of  its  kind  I 
ever  saw. 

Suppose  you  were  going  to  photograph  the  "  Harvesters  at  Rest."  You  would  choose 
the  shady  side  of  a  shock  of  sheaves ;  you  would  pose  the  tired  husbandman. in  a  restful 
attitude;  you  would  send 
the  housewife  to  him  with 
his  noon-day  lunch,  and, 
of  course,  she  must  bring 
the  baby,  because  there  is 
no  one  at  home  to  leave 
it  with.  The  mother  and 
child  should  be  placed 
where  the  husbandman 
can  admire  them,  and  thus 
help  him  rest  better,  where 
they  will  help  most  in  your 
diagonal  composition.  The 
basket  you  would  use  also 
to  complete  the  exterior 
lines  and  toss  the  old  hat 
down  where  it  would  best 
break  up  the  empty  fore- 
ground, and  break  up  a  

rather  too  broad  expanse 

of  light;  would  you  not?  Or,  if  you  are  in  a  grass-growing  country,  where  it  is  the 
custom  to  blow  the  horn  to  call  to  lunch  the  mower  and  the  good  wife,  who  tosses  the 
new-mown  hay,  that  it  may  dry  in  the  sun,  another  group  would  come  to  your  mind, 
such  as  "Answering  the  Horn,"  by  Mr.  Winslow  Homer  (Fig.  206).  Now  you  might  see 
a  dozen  such  couples  as  this  in  a  day's  ramble,  looking  awfully  picturesque,  and  yet  you 


206 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  205. 


(photographically  less  perfect),  in  which  any  of  the  changing  effects  of  light  and 
shade  may  have  been  successfully  rendered.  The  artist  should  likewise  con- 
sider that  careful  and  dis- 
criminating selection  will 
make  itself  felt  in  this  as 
in  every  other  description 
of  subject,  and  must  not  go 
out  with  his  camera  as  to  a 
sort  of  photographic  battle, 
in  which  one  well  studied 
picture  seems  not  to  be  the 
desideratum,  but  quantity 
not  quality  is  sought  for. 
Now  the  truth  is,  that  one 
little  bit  of  well  selected 
foreground,  a  bank  with  a 

would  be  puzzled  to  know  how  to  pose  them,  unless  you  could  invent  a  story  to  work 
them  into.  "Answering  the  Horn,"  does  it.  The  parties  halt  at  the  sound ;  the  answer- 
ing hand  goes  up  with  a  shout  from  the  mouth  of 
the  man,  which  closes  that  of  the  woman,  and  the 
picture  is  worthy  of  the  camera. 

In  attempting  larger  groups,  as  "  The  Washing 
Place— Brittany"  (Fig.  207),  by  Mr.  E.  M.  Ward, 
or  any  group  where  the  figures  are  numerous,  the 
effort  should  be  to  give  variety  to  the  ocupation  of 
the  persons,  and  with  them  all  and  what  accessories 
you  can — tell  the  story  to  the  best  of  your  ability. 
This  is  not  an  American  or  English  picture,  or  one 
likely  to  be  found  in  either  America  or  England, 
but  it  is  full  of  sugestion  all  the  same. 

The  next  illustration  will  be  more  "  to  the  manor 
born."  It  is  Mr.  Edward  Gay's  "  Penfield's  View" 
(Fig.  208),  and  is  from  a  celebrated  spot  beloved 
by  artists  near  Mount  Vernon,  New  York.  I  am 
sorry  the  reduction  is  so  small,  but  there  is  enough 
of  it  to  show  that  the  painter  was  influenced  by 
the  rules  of  art,  though  he  has  applied  to  nature 
to  give  him  the  means  of  securing  variety  and 
originality  in  his  work.  The  arrangement  of  the 
wagons  and  carts  and  people  and  sheep  was  by  no 
means  accidental,- but  intentional  in  a  great  meas- 


FIG.  206. 


OUTDOOR    OPERATIONS. 


207 


FIG.  207. 


few  docks  and  thistles,  with  the  bright  sun-ray  glancing  from  the  tufted  grass 
to  the  gray  ivy-grown  stump  of  the  gnarled  pollard,  is  worth  a  hecatomb  of 
such  things. 

ure,  though  he  has  evidently  a  quick  eye  enough  to  guide  him  in  taking  advantage  of 

accidental  arrangements,  and  the  power  of  methodizing  his  ideas.     All  these  you  must 

acquire  by  study   and  hard 

practice. 

"  Cannot  drive  sheep  where 

you  want  'em    in  a  photo- 
graph," you  say  ? 

Well,  I  have  seen  sheep 

better  grouped  in   a  photo- 
graph than  these  are.     It  is 

this  class  of  photographs,  my 

friends,  that  is  going  to  lift 

your  art  up  to  the  top  of  its 

ladder.     Remember  what   I 

say. — C.  WALTON  HILL. 
It  is  to  be  feared  that  much 

of  the  indulgence  in  extra. 

neous  appliances  is  the  result 

of   doing  the  work  by  the 

easiest  methods,  irrespective 

of  truth  and  taste.     If  there 

be  difficulties  in  any  department,  let  us  fight  with  them,  and  not  resort  to  spurious 

methods  because  they  happen  to  be  easier  or  more  convenient. 

I  have  always  regarded  photographic  art  and  its  requirements  as  being  more  allied  to 

dramatic  art  than  to  that  of 

FIG.  208  fine  art.     For  the  construction 

of  a  scene,  having  several 
figures  in  it,  see  how  carefully 
the  arrangement  of  them  has 
been  made  by  actors,  each  in- 
dividual, each  group  of  figures, 
varying  in  position  and  action, 
and  this  every  night  repro- 
duced because  the  subject  has 
been  fully  felt  and  understood. 
I  do  hope  the  day  is  not  far 
distant  when  stage  effects  may 
be  photographed.  Indeed,  it 
would  be  worth  the  effort  if 
rehearsals  were  made  in  the 

open  air,  under  sunlight,  and  during  the  course  of  action  instantaneous  impressions  taken. 

— NORMAN  MACBETH,  R.S.A. 


208 


WILSON'S    QUARTER    CENTURY    IX    PHOTOGRAPHY. 


I  have  selected  two  pictures  bearing  as  much  contrast  to  each  other  as  pos- 
sible, in  order  to  illustrate  my  point.  The  first  is  "  Noonday  in  the  Pasture," 
by  A.  D.  Shattuck  (Fig.  205),  and  the  other  an  ideal  landscape  (Fig.  209). 


FTO.  209. 


There  are  always  difficulties  and  drawbacks  in  out-door  work,  so  that  it  is 
seldom  that  a  photo-landscape  is  quite  perfect  as  a  whole,  though  exquisite  in 
the  detail  of  its  parts;  and  when  by  dint  of  careful  selection  and  study,  any- 
thing approaching  a  satisfactory  result  is  attained,  it  should  be  valued  in  pro- 
portion to  the  difficulties  overcome. 

There  is  much  to  encourage  work  and  effort  in  this  most  delightful  branch 
of  our  art.  The  great  mistake  which  many  have  made  who  have  aspired  to 
success  has  been  in  supposing  that  any  bit  of  landscape  which  might  happen  to 
present  itself  conveniently  to  the  camera  would  "  make  a  picture."  This  is  a 
fatal  blunder,  and  has  wrecked  the  hopes  of  many  a  one  without  his  having 
'any  knowledge  of  the  cause.  Be  encouraged  to  try  again. 


OUTDOOR    OPERATIONS. 


209 


FIG.  210. 


-e- 


94.  A  hundred  and  one  expedients  are  resorted  to  in  the  practice  of  photog- 
raphy outside  by  those  to  whom  necessity  has  revealed  them.     It  would  require 

94.  My  manner  of  getting  several  pictures  on  one  plate  is  in  certain  respects  quite  my 
own,  and  in  all  is  original  with  me,  though  subsequent  to  having  had  it  made  for  myself 
I  found  that  J.  E.  Johnson,  the  inventor  of  the 
pantascopic  camera,  had  anticipated  the  principle 
and  had  made  a  multiplying  front,  on  it. 

It  may  be  applied  to  any  form  of  camera,  but 
I  invariably  use  a  square  one,  which,  after  trying 
several  forms,  I  find  to  offer  the  greatest  conve- 
niences. But  whatever  the  form,  the  camera 
front  must  be  nearly  or  quite  the  size  of  the  plate ; 
as  will  be  seen  by  the  diagram  (Fig.  210),  FFis 
the  front  of  the  camera,  supposed  to  be  here  of 
the  same  size  as  the  plate  to  be  worked,  as  shown 
in  NN,  Fig.  211.  A  A  is  a  rabbeted  frame 
screwed  on  to  FF  and  raised  half  an  inch  or  so 
from  it,  so  as  to  allow  the  smaller  frame  B  B  to 
slide  up  and  down  in  the  rabbets  at  each  side ;  a 
small  brass  spring  at  each  end  of  B  B,  sufficing 
to  keep  it  at  any  given  point  by  its  pressure.  At  top  and  bottom  of  B  B  are  attached 
narrow  gussets,  like  those  of  the  bellows-camera,  but  very  thin,  so  that  as  the  frame  B  B 
moves  up  and  down  in  A  A,  the  lenses,  which  are  on  a  movable  panel,  PP,  fastened  into 
BB\)j  studs  and  buttons,  may  range  from  a  point  a  little  less  than  a  quarter  of  the 
height  of  the  plate  from  its  upper  edge  to  about  the  same  distance  from  its  lower,  so  that 

it  will  answer  as  a  sliding  front  for  the  horizontal 
halves  of  the  plate  as  well  as  for  the  whole  plate. 
The  camera  is  fitted  with  internal  gusset-par- 
titions, as  shown  in  Fig.  211,  the  longer  one, 
C  C,  being  capable  of  dividing  it  into  two,  ver- 
tically or  horizontally;  the  side  slips  S S  being 
arranged  to  divide  these  sections  into  two  each, 
as  shown  in  Fig.  211.  The  flanges  of  the  lenses 
are  screwed  on  the  panel  or  on  a  set  of  panels, 
one  for  each  flange  or  pair  of  flanges,  if  small 
views  or  stereoscopes  are  wanted,  and  the  panels 
can  be  changed  at  a  moment's  notice. 

As  will  be  seen  from  the  diagram,  Fig.  211, 
the  main  partition  will  give,  when  placed  at  (7(7, 
two  vertical  pictures  simultaneously  on  the  lateral 
halves  of  the  plate,, using  a  pair  of  lenses;  if 
placed  at  SS,  with  one  lens  in  the  position  of  L,  in  Fig.  210,  it  will  give  two  horizontal 
views  by  successive  exposures,  with  admirable  effect  for  panoramic  pictures,  as  the  camera 

14 


Fro.  211. 


C1  ' 

N 

1  1 

II 

II 

II 

II 

II 

S  _ 

:=:=::JJ^ 

_  S 

II 
II 

ii 

H 

II 

II 

N 

d! 

210        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

a  long  chapter  to  detail  them.  The  ingenuity  of  the  landscape  photographer 
who  is  determined  to  succeed  will  not  forsake  him  in  emergencies.  Apparatus 
makers  have  most  generously  met  whatever  requirements  have  been  made 

may  be  turned  round  to  match  the  two  halves  of  the  negative  together.  In  this  way,  with 
a  five  inch  focus  wide-angle  lens,  one  may  get  on  one  plate,  8x8  inches,  two  views  fairly 
matched  in  exposure  with  the  same  development,  which  will  include  180  degrees  on  the 
finished  prints  mounted  as  one.  Or  by  putting  the  main  partition  horizontally,  with  one 
of  the  short  partitions  below,  the  upper  half  of  the  plate  may  be  given  to  one  view  and  the 
lower  half  to  a  stereoscopic  negative.  In  this  case  all  three  flanges  should  be  on  one  panel, 
as  suggested  in  practice  by  Mr.  Taylor,  of  the  British  Journal  of  Photography,  who  adopted 
my  plan  and  improved  it  by  this  arrangement  of  the  lenses  on  one  panel.  (Care  must  be 
taken  that  the  wrong  lens  is  not  uncapped  by  accident  or  mistake.)  Or  by  the  use  of  all 
the  partitions  we  have  two  stereo  negatives,  necessarily  duplicates,  with  wet  collodion, 
but  of  different  subjects  if  working  dry  plates,  or,  with  four  exposures,  we  may  have  four 
views  of  widely  sundered  subjects  on  one  dry  plate. 

This  arrangement  also  gives  me  a  mathematically  precise  method  of  testing  the  com- 
parative sensitiveness  of  dry  plates,  by  coating  the  two  halves  of  a  full-sized  plate  with 
the  different  preparations  to  be  tried,  and  putting  them  vertically  into  the  holder,  so  that, 
with  a  pair  of  similar  lenses,  I  can  get  simultaneous  exposures  on  the  two  slips  of  glass ; 
giving  the  maximum  exposure  on  one  end  and  the  minimum  on  the  other.  This 
arrangement  gives  also  the  greatest  range  of  sliding  front  which  can  be  got  on  any  given 
camera. 

The  front  of  the  camera  must  be  fixed  rigidly  at  right  angles  to  the  bottom  and  the 
front  and  back  parallel,  when  using  the  partitions  for  duplicate  negatives,  or  the  focus 
must  be  adjusted  for  each,  which  perhaps  would  not  be  lost  time  on  the  whole. 

In  my  camera  the  wood  of  the  frame  A  A,  at  the  sides,  is  only  half  the  thickness  shown 
in  the  diagram,  or  to  the  dotted  line,  and  instead  of  being  rabbeted  has  a  brass  slip 
screwed  on  it  on  the  face.  This  is  stronger  with  the  same  weight.  The  inner  front  of 
the  camera  should  be  open  as  far  as  the  outer  edges  of  the  flanges  L  L,  and  the  inner 
surfaces  carefully  blackened,  to  prevent  light  turning  the  corner. — W.  J.  STILLMAN. 

There  is  in  the  minds  of  many  photographers  the  thought  that  it  is  possible  to  combine 
two  or  more  negatives,  and  join  them  together  perfectly  ;  that  by  a  careful  arrangement 
of  the  camera,  a  building  or  view  may  be  photographed  in  sections,  and  so  joined  together 
that  all  the  lines  and  points  will  fit  perfectly. 

Combinations  of  that  kind  have  apparent  correctness,  but  are  false,  in  truth.  All 
objects,  to  be  drawn  truthfully,  or  photographed  correctly,  must  be  made  as  seen  by  the 
human  eye.  But  by  this  method  of  making  pictures,  embracing  an  angle  of  90  degrees, 
in  sections  of  30  degrees  each,  there  is  a  change  of  the  point  of  sight  as  well  as  the  hori- 
zontal line.  The  perspective  of  the  photograph  must  therefore  be  false.  In  making  a 
view  including  an  angle  of  90  degrees,  the  base  line  is  central  to  the  view ;  but  in  the 
sectional  view,  the  axis  of  the  lens  is  turned  obliquely  to  the  two  wings  of  the  object,  and, 
of  course,  the  perspective  is  changed. 

In  some  subjects,  there  would  be  one  part  parallel,  and  the  other  parts,  in  very  acute 


OUTDOOK    OPERATIONS. 


211 


known  to  them  in  producing  most  exquisite  cameras,  light  tripods  (from  which 
spare  me),  rapid  exposing  shutters,  and  objectives  with  angle  so  wide  that  it  is 
dangerous  to  stand  alongside  during  exposure,  lest  you  be  caught.  There  are 

perspective,  dependent  upon  the  nearness  of  the  object  to  the  lens;  and,  of  course,  it 
would  make  an  absurd  picture. 

Fig.  212  is  supposed  to  represent  a  stone  wall,  as  seen  in  correct  perspective.  The  wall 
is  parallel ;  and  after  marking  one  section  parallel  to  the  wall,  the  camera  is  turned  to 
the  right,  with  the  following  result.  The  dark  dotted  line  marked  B  L  is  the  base  line, 
and  location  of  the  camera  in  both  views. 

FIG.  213. 


Fig.  213  represents  a  section  of  a  brick  wall.  Now,  who  would  suppose  such  a  result 
could  be  made  from  a  wall  that  is  parallel  ?  But  the  base  line  will  show  that  to  be  the 
case.  Could  anything  be  less  like  the  truth  than  this  ?  Yet  it  is  the  exact  appearance 
that  would  be  presented  from  a  given  point  by  the  camera  to  the  wings  of  the  view.  The 
line  H L,  HL,  is  the  horizon  line;  P  W,  P  W,  P  W,  is  a  parallel  wall;  PS,  the  point 
of  sight. 

Ridiculous  as  this  diagram  seems,  it  might  be  made  still  more  so  by  still  further  exag- 
gerating the  perspective.  The  camera  would  make  just  such  a  perspective,  if  the  view 
was  made  in  three  sections,  and  at  the  given  angle  of  the  diagram. 

Fig.  214  is  more  instructive  than  either  Fig.  212  or  .213,  as  it  explains,  I  think,  the 
difficulty  that  is  frequently  met  in  the  course  of  our  work. .  This  diagram  represents  a 
storehouse  which  I  was  obliged  to  photograph 
in  two  sections,  as  the  street  was  too  narrow 
to  do  it  on  one  plate.  It  was  then  joined  to- 
gether, with  the  above  result.  The  dotted 
lines  are  the  perspective  lines  of  the  first  pic- 
ture. It  will  be  noticed  that  the  vanishing 
point  is  outside  of  the  picture.  The  crossed 
lines  are  the  perspective  lines  of  the  second 
picture.  The  vanishing  point,  it  will  be  seen,  is  in  the  picture.  But  in  the  picture  on 
the  left,  it  is  taken  at  a  much  less  acute  perspective,  and  the  vanishing  lines  are  far  out 
of  the  picture.  This  shows  very  clearly  the  impossibility  of  making  a  building  in  two 
sections,  and  combining  them  so  as  to  give  correct  perspective. 


FIQ.  214. 


212 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


but  few  things  unprovided  for.  One  of  these  is  a  simple  and  cheap  apparatus 
for  making  panoramic  views.  Of  course,  we  all  know  of  the  Johnson  pano- 
ramic or  pantascopic  camera,  which  moves  the  objective  laterally  over  the  plate 
during  exposure,  but  it  is  intricate  and  expensive. 

95.  Exposing  shutters  are  offered  in  great  abundance  now,  so  compact,  so 
ingenious,  and  so  complete  as  to  enable  the  operator  to  regulate  the  exposure 
quickly,  at  will,  to  suit  the  light  and  subject  of  the  occasion. 

If  a  ruler  is  tried  on  the  drawing,  it  will  be  found  that  the  lines  above  the  horizon  are 
heaped  up  where  they  join,  while  those  below  are  crushed  down,  looking  slightly  con- 
cave.— JOHN  MORAN. 

95.  My  shutter  is  simple,  cheap,  and  sure.  Fig.  215  shows  the  shutter  complete,  ready 
for  action.  The  string  runs  through  an  opening  at  the  top,  and  may  be  of  any  length. 

The  case  for  the  shutter  may  be  of  tin  or  cardboard.    The 
,         ,      ,,  ,       -_      .    .       J  Fro.  217. 

drop  should  be  of  Russia  iron  or  copper. 

FIG.  215.  FIG.  216. 


\ 


Fig.  216  has  the  sliding  front  removed  to  show  the  drop. 
It  is  suspended  in  the  picture  about  two-thirds  of  its  proper 
height.  It  works  in  the  slot  of  the  diaphragm,  and  should 
work  very  freely.— WILLIAM  R.  WRIGHT. 

I  send  a  photograph  of  a  very  easily  made  shutter  of  my 
own  contrivance  (Fig.  217). 

Its  construction  will  be  understood  at  once.  I  find  it 
convenient  on  every  occasion.  It  will  act  instantaneously  if 
you  desire  it,  and  very  slowly  if  you  wish  it.  Moreover,  it 
is  easily  made  at  little  cost. — COL.  OTTAVIO  BARATTI. 

A  very  ingenious  stop,  invented  by  Mr.  Klein,  the  merit 
of  which  lies  in  its  great  simplicity,  as  well  as  in  its  perfect 
adaptation  to  the  end  to  be  obtained,  is,  viz:  The  motion  is 
given  by  an  India-rubber  string  (Fig.  218),  more  or  less 
distended,  according  to  the  duration  of  time  required.  The  opening  is  made  centrally, 
by  an  increasing  and  decreasing  motion.  The  mounting  of  this  stop  is  very  light,  and 
its  volume  does  not  exceed  19  x  12  centimetres  (7  J  x  4|  inches).  It  is  placed  before  the 


OUTDOOR    OPERATIONS. 


213 


The  matter  of  exposure,  however,  must  be  treated  separately  further  on. 
For  the  majority  of  subjects  the  well-known,  old-fashioned  "drop"  or  guillotine 


FIG.  218. 


FIG.  219. 


FIG.  220. 


FIG.  221. 


objective  by  means  of  three  screws ;  a  patch  of  black  cloth  attached  to  the  socket  of  the 
objective    prevents    the    introduction    of  any 
luminous  rays  except  those  which  penetrate  by 
the  opening  of  the  stop  itself. — LEON  VIDAL. 

Mr.  Quidde  has  made  good  suggestions  on 
the  action  of  instantaneous  shutters,  the  aper- 
tures of  which  are  of  different  shape.  He  gives 
the  following  diagram.  Fig.  219  shows  a  shutter 
with  a  circular  aperture  of  the  size  of  the  ob- 
jective. Fig.  220  shows  a  shutter  with  a  square 
aperture,  the  depth  of  which  corresponds  with 
the  diameter  of  the  objective;  and  Fig.  221 

shows  a  shutter,  the  aperture  of  which  is  wider  on  the  margins  than  in  the  centre.     The 
distance  from  a  to  b  is  equal  to  the  objective  diameter,  and  the  radius  of  the  circular  arc 

cad  and  ebf  equal  to  that  of  the  objective 
aperture.  If  the  three  boards  are  moved 
with  the  same  degree  of  rapidity,  the  time 
of  exposure,  in  regard  to  the  vertical  diameter 
of  the  objective,  will  be  identical  for  all  three 
boards,  for  all  three  have  to  move  the  same 
distance,  but  the  effect  of  the  light  differs 
very  much  with  all  three ;  a  moment  occurs 
in  which  the  whole  objective  is  free,  the 
effect  of  light  being  in  consequence  the  same 
with  one  as  with  the  others,  but  this  is  only 
for  a  moment ;  in  every  other  position  a  very 
material  diversity  is  manifested,  which  becomes  more  marked  at  the  beginning  or 
conclusion  of  the  exposure. 

In  the  above  diagram  the  moment  is  represented  when  the  top  edge  of  the  aperture 
has  arrived  in  the  centre  of  the  objective  opening.  In  Fig.  210  we  see  less  than  half  of 
the  objective  aperture  0;  in  Fig.  220  we  see  exactly  the  half,  and  in  Fig.  223  more  than 
half  of  the  objective  aperture.  The  difference  is  shown  in  a  still  more  striking  manner 
just  before  the  conclusion  of  the  exposure,  as  indicated  by  the  dotted  lines.  One  can 
easily  calculate  in  this  manner  that  the  effect  of  light  of  the  three  shutters  in  Figs.  219, 
220,  and  221,  with  equal  movement  and  all  other  circumstances  identical,  stands  in  the 
same  relation  as  the  superficial  contents  of  the  respective  apertures,  which  is  approxi- 
mately expressed  by  the  relation  of  the  numbers  11,  14,  and  17,  to  each  other.  The 
latter  form  of  shutter  is,  therefore,  the  most  advantageous,  for  it  exposes  the  margins  of 
the  picture  which  have  relatively  less  strength  of  light,  longer  than  the  centre.  Both 
other  forms  expose  the  margins  of  the  picture  too  short  a  time.  There  are  also  shutters 
in  which  two  boards  with  circular  apertures  pass  by  each  other.  Here,  again,  the  centre 


214         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


shutter  answers  admirably.  Of  course,  it  is  not  recommended  for  "  instan- 
taneous "  exposures  with  "  lightning  "  plates. 

of  the  objective  has  the  advantage  over  the  margins.  The  shutter  opens  in  the  centre, 
the  aperture  enlarged  toward  the  margins  until  it  has  reached  its  highest  possible  exten- 
sion, when  it  is  shut  all  at  once  again  from  the  margins,  so  that  in  case  the  aperture  of 
the  shutter  is  not  larger  than  the  objective,  it  may  be  said  that  the  time  of  exposure  of 
the  margins  of  an  objective  is  almost  too  short  to  count  at  all.  As  in  consequence  of  the 
introduction  of  highly  sensitive  plates  instantaneous  shutters  come  more  and  more  into 
use,  these  indications  are  of  special  interest  for  practical  men.  —  DR.  H.  W.  VOGEL. 

Lenses,  such  as  are  used  for  instantaneous  landscape  work,  are  almost  all  fitted  with 
diaphragms,  which  slide  into  the  body  of  the  tube  between  the  two  lenses.  I  believe  this 
system  is  known  as  the  Waterhouse  diaphragm  (see  Fig.  222,  1  and  2).  A  similar  slit  is 
made  in  the  under  portion  of  the  tube,  and  a  long,  thin  piece  of  steel,  with  a  hole  in  the 
centre,  replaces  the  ordinary  diaphragm  (Fig.  223).  After  having  focussed,  the  steel 
slide  is  placed  into  the  slit  and  held  in  an  upright  manner  by  means  of  a  catch  or  spring 
under  the  lens;  when  this  is  pressed  the  steel  slide  slips  rapidly  down  through  the 
grooves,  and  the  image  is  thrown  but  for  an 
instant  upon  the  sensitized  surface  in  the 
camera.  The  length  of  exposure  can  be 

FIG.  222. 


>  223' 


FIG.  224. 


FIG.  225. 


regulated  by  having  two  or  three  slides  with  different  openings  (Figs.  224  and  225).  If 
more  rapidity  be  required,  a  small  weight  can  be  attached  to  the  slide  by  means  of  a 
strong  silken  thread  (Fig.  225,  A).  If  this  is  insufficient,  a  number  of  small  metal  disks 
or  quoits  can  be  made  to  lay  on  the  top  of  the  weight  (Fig.  5,  j5).  No  shaking  of  the 
whole  apparatus,  as  with  the  old  system,  need  be  feared,  for  the  steel  slide  slips  through 
its  brass  guides  in  an  easy  and  uniform  manner,  and,  when  the  shock  arrives,  the  im- 
pression has  been  already  obtained.  The  shock  itself  can  be  softened  by  lining  the 
flange  at  the  top  of  the  slide  with  India-rubber,  or  by  some  mechanical  contrivance,  such 
as  P,  spring,  etc. — PROF.  E.  STEBBING. 

I  have  no  intention  of  recommending  any  particular  shutter ;  let  the  reader  exercise 
his  own  judgment  in  making  his  selection  ;  but  I  would  say  a  word  or  two  in  favor  of 
the  description  of  apparatus  I  think  the  best  for  nearly  all  possible  requirements  both  in 
studio  and  field  work. 


OUTDOOR    OPERATIONS. 


215 


96.  Even  with  the  Eastman  roll  holder  and  films,  which  enable  one  so 
comfortably  to  work  outside,  one  sometimes  finds  it  necessary  to  change  plates  or 

There  are  very  many  photographers  who  yet  make  exposures  in  the  studio  with  cap 
in  hand.  They  have  always  been  accustomed  to  it,  and  never  troubled  themselves  to  try 
any  other  way.  Let  me  advise  them  to  get  a  flap-shutter,  working  on  the  pneumatic 
principle,  and  I  have  no  doubt  they  will  be  so  well  pleased  that  they  will  never  do  with- 
out it  again.  To  expose  by  hand  ties  the  operator  close  to  the  camera  in  a  sort  of  side 
posture,  and  causes  him  inconveniently  to  divide  his  attention  between  the  physical 
operation  of  exposure  and  the  physical  eccentricities  of  the  subject,  which,  in  the  case 
of  a  child,  may  be  considerable  and  perplexing.  Whereas,  if  he  possesses  a  flap-shutter, 
which  he  can  open  and  close  at  once,  or  sustain  open  as  long  or  short  a  time  as  he 
pleases,  he  can  give  his  whole  care  to  the  little  sitter. 

As  to  field  work,  unless  an  express  train  be  the  subject,  which,  by  the  way,  is  seldom 
worth  the  trouble  of  taking,  or  a  galloping  horse,  extreme  rapidity  of  exposure  is  not 
wanted,  and  is  not  very  often  of  much  use  or  excellence  when  made.  The  quick  move- 
ment of  a  flap-shutter  is  perfectly  equal  to  most  occasions,  and  the  same  advantages 
which  accompany  its  use  in  the  studio  follow  it  to  the  field ;  while  in  addition  it  may 
easily  be  adapted  so  as  to  act  in  the  manner  of  a  sky  shade.  Such  a  shutter  should  be 
light  and  portable,  and  there  seems  no  good  reason  why  it  should  not  be  made  very  little 
larger  than  the  hood  of  the  lens. — G.  G.  MITCHELL. 

96.  A  modification  of  the  tent  for  working  dry  plates,  or  any  plates  that  are  only 
exposed  and  changed  in  the  field,  the  other  operations  being  reserved  for  home,  is  very 
simple  and  effectual.  Thus:  three  light 
rods  of  bamboo  or  other  material  are  re- 
quired— two  of  them  shod  with  iron  for 
driving  in  the  ground,  and  the  third  to  lay 
across  the  top,  and  fastened  to  each  upright 
by  pegs  or  otherwise.  When  these  are 
fixed,  a  large  sheet — impervious  to  light, 
except  at  a  window  let  into  the  material,  of 
yellow — is,  when  required  for  use,  thrown 
over  the  operator,  frame  and  all.  The 
window  is  allowed  to  fall  between  the  up- 
rights in  front,  to  supply  the  light  in  the 
proper  position.  The  operator  can  very 
easily  adjust  the  sheet  when  underneath  it, 
so  that  it  will  keep  out  the  white  light,  the 

frame  in  front  at  the  same  time  preventing  it  incommoding  him  during  the  process  of 
plate-changing.  When  not  required,  it  can  easily  be  folded  and  strapped  round  the 
plate-boxes  and  frame  for  carriage.  If  waterproof,  it  forms  a  capital  protection  during 
a  shower  of  rain. 

I  have  not  tried  a  sheet  made  expressly  for  the  purpose,  but  I  know  that  it  would 
answer  well  for  my  tent-covering;  and  a  branch  cut  from  the  nearest  tree  did,  when 


FIG.  226. 


216 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  227. 


"  spools  "  when  in  the  field  or  on  the  road.  For  such  a  necessity  a  number 
of  suggestions  have  been  made  (see  notes).  The  only  requirement  is  that  the 
place  where  the  changes  are  made  should  be  light-tight.  A  tripod  erect, 
covered  properly,  with  a  red  window  or  two,  the  material  sufficiently  long  to 
cover  the  "  floor,"  was  what  I  used  in  my  Oriental  adventures. 

97.  The  old-fashioned  tent  for  wet-plate  purposes  has  also  been  used  as  a 

used  in  a  similar  manner,  though  it  would  be  a  sorry  makeshift  compared  with  a  sheet 

constructed  expressly  for  the  purpose. 

Fig.  226.  A  A  A,  light  rods  of  bamboo  or  other  wood, 
made  to  peg  into  the  ground  and  form  a  frame,  supported 
by  the  struts  D  D,  which  are  hinged  to  the  uprights  A  A 
for  the  purpose  of  obtaining  rigidity.  B  is  a  window  of 
yellow  material.  CCCC,  pegs  for  the  purpose  of  fasten- 
ing the  cloth  to  the  ground.  D,  dark  slide.  E,  plate-box. 
— EDWARD  DUNMORE. 

I  find  the  annexed  (Fig.  227)  an  excellent  plan  of  con- 
structing a  photographic  changing  tent.  A  A,  upper 
arms  of  the  lower  braces,  may  be  hinged  stationary.  BB, 
lower  arms ;  table  butts  may  be  used  to  hinge  the  arms. 
C,  centre  pole,  triangular,  or  better  square.  D  D,  duck 
or  canvas,  lined  with  yellow.  A  A,  duck  or  canvas,  over 
the  upper  arms.  E,  stay  rope  at  the  bottom.  Tuck  in 
the  material  close  at  the  bottom. 
It  will  be  found  very  convenient,  especially  for  city  use.  It  can  be  set  up 'on  the 

street,  sidewalk,  platforms,  floors  of  cellars,  warehouses,  or  depots,  and  needs  no  staying 

if  sheltered  from  the  wind. — R.  M.  LINN. 
97.  The  accompanying  cut  (Fig.  228)  will  explain  itself. 

The  valise  is  made  of  T5ff  inch  bass  wood  or  pine,  and  meas- 
ures 25  inches  long,  15  inches  high,  and  10  inches  broad  on 

the  inside  when  closed.     It  contains  everything  but  the 

tripod  for  making  twenty-four  negatives.     I  use  no  water 

for  washing,   but  flow  the  plate   after   developing  with 

glycerine,  2  ounces;    acetic  acid,  4  ounces;  and  water,  6 

ounces;  and  put  the  plate  into  a  plate-box  to  be  intensified 

and  fixed  after  returning  home.    The  cover  is  made  of 

water-proof  (ladies'  cloaking)  lined  with  yellow  calico,  with 

two  thicknesses  of  the  calico  at  the  right  hand,  and  when  I 

receive  the  light  for  developing,  the  amount  of  light  is 

regulated  by  raising  the  water-proof  up,  and  pinning  the 

corner  more  or  less  as  necessary.     I  use  a  10  x  12  rubber 

pan  to  develop  over,  and  carry  my  developer,  saturated 

solution,  and  reduce  as  necessary.     The  valise  opens  in  halves,  so  that  the  part  raised 

up  perpendicularly  forms  a  shelf  for  the  bottles,  plate-holder,  etc.,  at  the  bottom.     I  have 


FIG.  228. 


OUTDOOR    OPERATIONS.  217 

changing-box.  And  not  to  forsake  an  old  friend,  I  must  mention  that  such 
"tents"  are  still  in  use  by  some  who  pertinaciously  adhere  to  the  "wet."  A 
hundred  suggestions  for  constructing  such  an  antique  convenience  have  been 
made.  I  trust  to  the  notes  to  provide  one  of  the  simplest  forms  for  all  that  is 
necessary. 

98.  A  great  deal  is  added  to  the  pleasure  of  receiving  a  view  from  a  friend, 
if  the  title  is  thereupon.  If  you  have  an  amateur  printing  press,  you  can  easily 
manage  it.  With  type  of  good  face,  not  too  bold,  set  the  title  and  print  with 
black,  dense  ink  upon  fine  "French  folio  post"  paper.  Render  the  slips 
transparent  by  soaking  in  Anthony's  "Diamond"  varnish.  Then,  with  a 

had  two  other  dark-tent  arrangements,  but  prefer  this  very  much,  being  light;  it  forms  a 
receptacle  for  necessary  things,  and  two  sides  of  the  tent  when  set  up. — IRVING  SAUNDERS. 
98.  To  show  the  possibility  of  dispensing  altogether  with  the  focussing-glass  and  cloth 
when  out  of  the  studio,  I  have  had  inserted  into  the  back  of  the  camera  an  oculaire,  or 
eye-piece,  like  that  of  a  microscope.  In  order  to  find  the  focus  once  for  all,  a  ground- 
glass  is  inserted  into  the  place  of  the  dark-slide.  The  centre  of  this  ground-glass  is 
polished  and  marked  as  a  chessboard,  by  means  of  a  fine  diamond.  A  newspaper  is 
placed  before  the  lens,  and  its  image  is  therefore  reflected 
on  the  ground-glass.  This  oculaire  is  drawn  in  and  out 
until  the  image  of  the  letters  and  the  diamond  marks  are 
both  perfectly  sharp.  When  this  result  is  obtained  it 
suffices  to  fix  the  oculaire  in  its  case  or  telescopic  tube  by 
means  of  a  screw,  or  to  make  a  mark  round  its  circum- 
ference, so  that  the  same  place  can  easily  be  found  again 
when  required.  It  is  true  that  only  the  central  part  of 
the  view  can  be  focussed  in  this  manner,  but  in  practice 

it  Suffices  ^'  brass  semicircle  divided  into  degrees. 

Not  having  a  focussing-glass,  it  may  be  asked,  How  £  ^upon  which  the  alidade  is  fixed. 
can  the  operator  know  the  length,  breadth,  and  depth  of 
the  image,  as  reflected  on  his  sensitized  plate?  The  answer  is,  every  person  knows  the 
angle  of  his  lens.  So  I  conceived  the  idea  to  have  a  little  instrument  placed  upon  the 
top  of  the  camera.  (See  Fig.  229.)  Supposing  the  angle  taken  in  by  the  lens  to  be  30 
degrees,  the  alidade  or  hand  is  moved  toward  the  right  hand  until  it  lies  upon  the  15 
degrees  of  the  semicircle.  Now,  in  looking  along  it,  the  operator  can  easily  see  what  he 
takes  in  on  the  right-hand  side  of  his  camera.  The  alidade  is  then  turned  to  the  left, 
until  it  lies  on  15  degrees.  What  will  be  reproduced  upon  the  sensitized  plate  can  thus 
be  easily  seen.  In  order  to  know  whether  or  not  too  much  sky  or  otherwise  will  be  taken 
in,  another  similar  instrument  is  placed  on  the  side  of  the  camera. — LEON  VIDAL. 

I  compliment  Mons.  Vidal  for  having  found  means  to  focus  without  a  ground-glass, 
for  most  landscape  photographers,  whether  amateur  or  the  trade,  have  known  the  incon- 
venience of  a  broken  focussing-glass.  But  I  beg  Mons.  Leon  Vidal's  pardon  for  suggest- 


218 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  230. 


camePs-hair  pencil  lift  them  to  the  negative  and  carefullly  place  them,  using 
more  varnish  if  necessary  to  make  them  adhere.  It  will  be  seen  at  once  that 
the  title  will  print  with  the  picture. 

ing  a  slight  change,  not  in  the  focussing,  but  in  the  means  of  taking  the  angle,  which  I 
think  is  a  little  too  complicated.  I  would  propose  a  kind  of  instrument  as  given  in  Fig. 

230.  If  this  instrument  be  placed  on  the  top  of 
the  camera,  and  the  eye  of  the  operator  be 
placed  close  to  the  opening  D,  in  looking 
through  the  metallic  frame  C,  the  whole  of  the 
view  embraced  by  the  angle  of  the  lens  can  be 
seen  at  once,  and  the  camera  moved  about 
until  the  most  pleasing  and  artistic  part  of  the 
landscape  is  in  view.  Let  it  be  supposed  that 
the  distance  from  the  eye  to  the  frame  coin- 
cides with  the  angle  of  the  lens.  In  fact,  it 

A'  A,  two  pieces  of  brass  or  wood.  Can  be  US6d  Wlth  **?  lenS>  f°r  lf  &  Sh°rt  f°CUS 

B,  a  plug  or  drawer  to  enable  the  two  pieces,  A'  A,    one  be  employed,  there  is  only  to  approach  the 

approach  each  other,  or  vice  versa.  visual  hole  D  to  the   frame  C]   if  a   long  foCUS 


FIG.  231. 


wing  four  silken  threads  dis-    lens    be   required     the  two  supports    are  to   be 
secting  it  like  a  chess-board. 

A  a  hole  for  the  eye  to  look  through.  drawn  asunder  as  far  as  required.     The  frames 

C  and  D  can  be  joined  to  A/  A  by  hinges,  so 

when  not  in  use  they  can  lie  down  flat,  which  will  be  very  convenient  for  packing. — 
PROF.  E.  STEBBING. 

If  the  attempt  is  made  to  photograph  bright  objects  with  dark  surroundings  in  the 
same  picture,  failure  in  one  or  other  is  quite  certain ;  and  yet  the  artist  is  induced  to  try 
it,  as  the  object  is  beautiful,  and  he  may  never  see  it  again ;  or  if  he  can  wait  till  he  has 
no  sunshine,  he  knows  he  will  get  only  a  flat,  unrelieved  picture.  I  herewith  send  you 
a  drawing  of  such  a  supposed  case,  and  my  remedy,  which 
I  have  found  very  successful,  indeed,  much  more  so  than  I 
expected  it  would  be.  It  consists  of  a  split  sunshade  (one 
of  which  I  have  roughly  made  and  send  you).  The  shade 
is  divided  into  three  separate  flaps,  as  shown  in  Fig.  231 ; 
these  are  all  loose  or  tightened  in  any  position  by  the  screw 
*.  The  size  and  division  of  such  a  sunshade  will  require  to 
be  adapted  by  the  optician  to  different  lenses,  according  as 
the  lens  is  large  or  small  in  aperture,  yet  only  as  to  distance 
from  the  optical  centre. 

The  use  of  such  a  sunshade  will  be  at  once  apparent.  In  my  sketch  the  camera  (of 
ccourse  disproportionately  large  and  not  in  exact  position)  is  trying  to  take  a  white  stone 
mansion  surrounded  by  dark  trees.  In  ordinary  circumstances  the  house  will  cither 
come  out  a  white  patch  with  black  holes  for  windows,  and  the  roof,  if  slate,  impenetrably 
mingled  with  the  sky,  or  the  trees  and  grass  will  present  an  outline  inclosing  a  black 
apace  without  foliage  or  detail.  But  now  the  camera  says — "  I  have  got  three  eyelids 


OUTDOOR    OPERATIONS. 


219 


I  do  not  pretend  to  have  covered  the  ground  entirely  in  this  chapter.  The 
faculty  of  observation  should  be  cultivated  by  every  live  camera  lover.  I 
never  saw  another  person  at  work  without*  learning  something  from  him. 

instead  of  one;  and  if  I  wink  a  little  with  the  centre  one  whilst  I  keep  the  two  outer 
ones  wide  open,  I  can  gain  a  minute  or  two  on  the  dark  sides  and  grass  before  I  open 
upon  the  white  house  for  thirty  seconds."  "  But  how  will  the  image  come  out?  What 
about  the  shadow  of  my  lower  eyelid  on  one  portion  of  the  picture  ?"  Well,  I  shared 
my  camera's  fear  on  this  point,  and  thought  it  might  have  been  necessary  for  him  to  keep 
winking  and  moving  his  eyelid,  to  prevent  a  line  or  marked  division  in  the  picture.  I 
find  to  my  delight  it  is  not  so.— REV.  ST.  VINCENT  BEECHEY. 

"THE  INDISPENSABLE."  I  find  this  device  made  plain  by  the  cuts,  in  a  French 
paper.  This  support,  for  cameras,  which  has  a  clamp  joint,  allows  the  apparatus  to  be 
placed  in  all  possible  positions,  even  in  the  reverse  position  (aerostatic  photography),  in 

FIG.  232. 


fact,  in  all  cases  in  which  the  use  of  the  tourist's  tripod  is  inconvenient  and  even  impos- 
sible. The  facility  with  which  it  can  be  solidly  attached  to  the  top  of  an  ordinary  ladder, 
allows  the  landscape  photographer  who  possesses  this  appliance,  to  do  away  with  the 
annoyance  and  impediment  of  the  tripod  stand. — C.  J.  W.  in  the  Moniteur. 

After  varnishing  I  cut  my  stereo  negatives,  and  fasten  on  other  glass  at  the  edges 
with  gummed  paper,  placing  the  right-hand  picture  on  the  left  side,  to  save  the  trouble 
of  transposing  the  prints  in  mounting. 

The  negatives  I  keep  in  long  grooved  boxes  set  up  one  on  the  other  like  shelves.  Each 
negative  is  numbered  from  1  up,  and  has  its  corresponding  place  in  the  box.  I  have  a 
large  book  containing  the  views  arranged  in  numerical  order  (extremely  handy  to  select 
from  and  in  making  out  printing  lists),  and  large  cupboards  with  pigeon-holes  arranged 
in  the  same  way  to  contain  the  finished  pictures. — S.  R.  STODDARD. 


CHAPTEE   XI. 

EXPOSURE,  OR   THE   QUESTION   OF   TIME. 

99.  To  secure  the  right  exposure  of  the  plate  in  the  camera,  always,  has 
puzzled  the  wisest  of  photographers.  It  continues  to  do  so.  But  the  reasons 
have  changed.  With  emulsion  photography  the  danger  is  in  over-exposure, 
while  "in  old  wet  days"  the  difficulty  was  to  secure  enough.  All  sorts  of 
methods  were  resorted  to  in  order  to  accelerate  the  exposure. 

All  those  old-time  methods  have  fallen  into  "  innocuous  desuetude."  Never- 
theless it  may  be  interesting  to  mention  them  here,  though  without  any 
attention  to  chronological  order. 

Mr.  Charles  Waldack  recommended  the  action  of  diffused  light  upon  the 
plate  for  very  short  exposures.  This  was  an  old-time  Daguerrotype  dodge. 

Mr.  Ernest  Krueger  advocated  a  secondary  illumination — for  example,  after 
the  plate  had  been  exposed  to  the  subject  say  one  second,  a  red-colored  paper 
was  -held  for  some  seconds  before  the  objective  and  thus  was  obtained  as  good 
a  result  as  with  a  six  times  longer  exposure  to  the  model. 

99.  A  recent  writer  says:  "The  time  of  exposure  must  often  be  guessed  at  in  the 
vaguest  manner,"  and  again,  "then  in  our  uncertainty  about  strength  of  light  and  stops." 

If  this  view  of  the  subject  be  general,  it  is  not  surprising  that  the  guessing  should  be 
so  often  wide  of  the  mark.  Although  T  will  not  assert  that  absolute  precision  is  attain- 
able until  we  have  a  perfect  actinometer  (which  we  shall  soon  have),  I  will  say  that  with 
care  and  calculation  a  degree  of  accuracy  and  certainty  is  possible  of  which  many  have 
not  dreamt. 

The  most  important  conditions  are  six  in  number,  viz.,  Diaphragm,  Light,  Time  of 
Day,  Time  of  Year,  Plate,  Subject. 

Diaphragm :  The  rapidity  of  a  lens  is  governed  by  its  aperture  and  focus.  As  the  in- 
tensity of  the  light  from  any  lamp  or  window  is  four  times  as  great  at  one  foot  as  it  is  at 
two  feet,  so  the  intensity  or  brilliancy  of  an  image  on  the  focussing  screen  is  four  times 
as  great  at  six  inches  as  it  is  at  twelve  inches  from  the  lens,  the  aperture  of  the  lens 
being  the  same.  And  as  the  area  of  a  circle  of  two  inches  diameter  is  four  times  that  of 
one,  one  inch  in  diameter,  so  a  lens  of  six  inch  focus  and  one  inch  aperture  will  have  the 
same  intensity,  and  consequently  require  the  same  exposure  as  a  lens  of  twelve  inch  focus 
and  two  inch  aperture.  It  is  simply  a  question  of  the  relation  the  aperture  bears  to  the 
focus  and  is  easily  determined  with  the  utmost  exactitude.  But  if  any  one  thinks  that 
(220) 


EXPOSURE,    OR    THE    QUESTION    OF    TIME.  221 

Henry  Grosshof,  after  the  exposure  in  the  skylight,  gave  an  auxiliary 
exposure  in  the  dark-room  to  a  petroleum  lamp  whose  light  came  through  a 
ground-glass. 

Mons.  Bogin  proposed  to  reduce  exposure  by  placing  in  the  camera-front 
cells  containing  a  red  liquid,  thus  securing  the  admission  of  red  light  to 
the  film. 

Dr.  M.  Carey  Lea  colored  pieces  of  cardboard  with  carmine  and  lined  the 
least  illumined  parts  of  the  camera  with  them. 

Mr.  Blair  recommended  lining  the  camera  with  white  card. 

Mons.  Scotellari  proposed  the  use  of  extraneous  violet  light. 

Mr.  Charles  Gutzlaff  proposed  bichromate  liquids  as  a  means  of  securing 
extraneous  light  to  be  used  similarly. 

Mons.  Blanquart  Evrard  proposed  to  reduce  the  exposure  by  using  what  he 
called  the  light  camera  (chambre  claire),  a  camera  which  had  been  painted  white 
on  the  inside.  The  light  of  the  parts  of  the  image  on  the  edges  of  the  field 
would  then  strike  the  white  sides  of  the  camera  and  be  reflected,  thus  producing 
a  much  more  brilliant  image  on  the  ground-glass ;  and  as  a  consequence,  a 
shortening  of  the  exposure. 

two  and  two  make  five,  let  him  think  so  and  go  on  guessing.  If  the  actinic  value  of  light 
could  be  as  easily  determined  as  the  diaphragm,  there  would  then  be  only  one  important 
condition  left  for  the  exercise  of  judgment,  viz.,  the  subject. 

But  since  we  have,  as  yet,  no  instrument  from  which  we  can  read  at  a  glance  the 
actinic  value  of  light,  we  shall  have  to  get  at  it  in  a  somewhat  roundabout  way,  by  esti- 
mating the  apparent  brightness  of  the  light,  and  then  at  its  photographic  value  by  a 
consideration  of  the  time  of  day  and  time  of  year.  Until  we  have  the  perfect  actino- 
meter,  which  shall  give  us  the  measurement  of  light  in  degrees  as  a  thermometer  meas- 
ures temperature,  it  will  be  convenient  to  describe  the  light  on  the  subject  as:  very 
bright  (sun  or  cloud),  bright  (sun  or  cloud),  bright  haze,  overcast,  dull,  and  very  dull. 
Now  let  each  of  these  conditions  of  light  be  measured  by  an  ordinary  actinometer  (which 
every  one  had  best  do  for  himself)  and  their  relative  values  noted  for  future  reference. 

Time  of  day :  You  are  aware  that  within  two  hours  of  sunrise  and  sunset  the  photo- 
graphic value  of  light  is  often  very  different  from  its  apparent  brightness,  that,  in  fact, 
the  light  is  very  yellow  near  sunrise  and  sunset.  A  very  good  clew  may  be  obtained  by 
a  consideration  of  the  time  of  day.  Some  use  a  table  showing  the  allowance  to  be  made 
for  each  hour  of  the  day  and  for  every  month  in  the  year.  This  answers  very  well,  but 
it  is  a  little  complicated.  A  simpler  and  more  scientific  method  is  to  measure  the  altitude 
of  the  sun.  This  can  be  done  with  sufficient  accuracy  with  a  common  tape-measure  held 
at  arm's  length.  Then  measure  with  a  common  actinometer  the  actinism  of  the  sun  and 
diffused  light  at  various  altitudes  from  the  horizon.  Taking  bright  midday  sun  as  one, 
we  will  find  the  sun  at  twenty-eight  degrees  above  the  horizon  is  relatively  1}  at  seven- 


222         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Mr.  F.  B.  Gage  proposed  in  cases  of  bad  illumination  and  underexposure,  to 
allow  the  light  reflected  from  the  black  velvet  camera  cloth  held  in  front  of  the 
lens  to  act  for  a  short  time  on  the  exposed  plate  This  proved  in  the  hands 
of  many  a  very  useful  dodge  in  making  portraits  of  children ;  but  it  is  quite 
forgotten  by  the  present  generation  of  photographers. 

Mr.  H.  J.  Newton  admitting,  it  is  supposed,  the  correctness  of  the  Becquerel 
theory  in  regard  to  the  continuatiug  action  of  the  red  rays,  allowed  the  light 
passing  through  a  red  glass  inserted  in  the  front  of  the  camera  to  act  on  the 
plate,  thus  obtaining  a  reduction  of  the  exposure. 

A  Paris  photographer  constructed  a  lens  cap  into  which  a  piece  of  violet 
glass  was  inserted,  allowing  the  light  to  act  through  it  on  the  sensitive  plate 
for  a  few  seconds,  and  he  succeeded  in  reducing  the  exposure  considerably. 

The  dodge  of  allowing  the  light  to  act  slightly  on  the  plate,  to  be  able  to  do 
with  a  shorter  exposure,  was  not  despised,  but  was  made  use  of  largely.  A 
means  often  used  was  to  cover  the  largest  stop  with  white  paper,  and  cut  out 
an  opening  the  size  of  the  stop  generally  used.  The  result  was  a  softer  nega- 
tive, with  one-third  or  one-half  less  exposure  than  if  the  opaque  stop  had 
been  used. 

teen  degrees,  2  at  thirteen  degrees,  4  at  ten  degrees,  6  at  seven  degrees,  12  and  so  on. 
This  will  give  value  for  both  time  of  day  and  time  of  year  at  once,  but  the  sun  may  be 
obscured  by  cloud,  or  the  horizon  may  not  be  visible.  Another  method  which  suggests 
itself  and  which  works  well  in  practice,  is  to  make  a  table  showing  the  hour  of  sunset 
for  each  month  in  the  year,  and  another  showing  the  relative  light  value  at,  say,  two 
hours  from  sunrise  and  sunset,  ninety  minutes,  sixty  minutes,  forty-five  minutes,  thirty 
minutes,  fifteen  minutes,  and  ten  minutes,  as  compared  with  midday  in  midsummer.  The 
rapidity  of  plates  must  be  measured  either  by  the  plate  maker  or  operator  with  a  sensi- 
tometer. 

The  subject  will  give  plenty  of  scope  for  the  exercise  of  judgment.  Subjects  should 
be  classified,  and  experiences  (both  successes  and  failures)  will,  if  noted,  give  valuable 
data  to  assist  the  judgment. 

We  have  decided  on  the  view  to  be  photographed,  the  exact  spot  which  will  give  us 
the  best  foreground,  planted  the  camera,  selected  the  lens  which  will  give  the  desired 
angle  of  view  we  wish  focussed,  decided  on  the  stop  to  be  used,  inserted  the  plate-holder, 
but  before  we  draw  the  slide  let  us  calculate  the  exposure  carefully  on  scientific  lines 
and  thus  save  any  quantity  of  plates  spoiled  by  incorrect  timing  and  oceans  of  time  con- 
sumed in  timid  development. 

As  a  basis  for  all  our  calculations,  we  will  suppose  that  we  have  ascertained  that  the 
correct  exposure  is  one  second  for  a  normal  subject,  which  will  be  a  landscape  with  light 
foliage  in  the  foreground,  with  a  plate  sensitometer  number  20  and  diaphragm  value/ 22 
full  sunlight.  This  is  the  standard  to  calculate  from. 


EXPOSURE,   OR    THE    QUESTION    OF    TIME.  223 

This  action  of  diffused  light,  lighting  up  the  image,  and  thus  reducing  the 
exposure,  often  takes  place  when  the  photographer  is  not  conscious  of  it.  Years 
ago,  when  it  was  customary  to  make  negatives  for  vignettes  against  a  white 
background,  it  was  found  the  exposure  was  considerably  reduced. 

Again,  the  image  may  be  lighted  by  reflection  from  the  sides  of  the  camera 
and  from  the  surfaces  of  the  lenses.  The  lighter  parts  of  an  image — the  sky, 
for  instance — will  reflect  diffused  light  on  the  inside  of  the  camera,  and  thus 
light  up  the  darker  parts.  Any  landscape  photographer  may  have  observed 
that  a  view  with  much  sky  will  require  a  less  exposure  than  one  from  which 
the  sky  is  nearly  excluded.  This  point  is  a  very  important  one  to  remember 
when  using  "  quick,"  or,  in  fact,  any  emulsion  plates.  Long  exposure  reduces 
contrast.  Suppose  we  have  before  the  camera  a  country  residence,  with  over- 
hanging porticos  illuminated  by  a  strong  summer  sun.  The  contrast  is  painful 
to  the  eyes ;  and  still,  by  giving  a  sufficiently  long  exposure,  we  can  reduce  it 
so  that  the  house  appears  to  be  bathed  in  the  mellow  light  of  an  Indian  summer 
day.  How  much  of  this  may  be  owing  to  the  diffused  light  reflected  from  the 
more  illuminated  parts  ? 

Example. — Subject,  open  view  with  heavy  masses  of  foliage  in  foreground — double  the 
standard  or  two  seconds. 

Stop,/ 30 — double  the  standard,  4  seconds. 

Plate,  sensitometer  number  16 — four  times  standard,  16  seconds. 

Time  of  day,  3  P.M.,  October — four  times  standard,  16  seconds. 

Light,  full  sun  with  patches  white  cloud ;  no  allowance ;  correct  exposure  32  seconds. 

Example  2. — Subject,  sea  and  sky — £  standard,  £  second. 

Stop,/ 16 — }  standard,  -^  second. 

Plate,  sensitometer  24 — i  standard,  ^  second. 

Time  of  day,  2  P.M.,  April — normal. 

Light,  light  sunshine,  hazy  sky — £  standard,  ^  second;  correct  exposure,  fo  second. 

Where  the  angle  of  lighting  is  unusual  or  extreme,  allowance  is  to  be  made  ;  for  in- 
stance, if  the  lighting  is  very  much  from  the  side,  the  exposure  should  be  the  same  as  for 
diffused  light,  as  the  golden  rule  is  to  expose  for  the  shadows  and  let  the  lights  take  care 
of  themselves;  this  rule  has  exceptions  of  course,  but  where  the  shadows  are  broad  they 
must  have  plenty  of  detail  always. 

It  will  frequently  be  found  at  midsummer,  especially  in  photographing  perpendicular 
objects  in  sunshine,  that  less  exposure  is  required  an  hour  or  two  before  and  after  mid- 
day than  at  midday ;  not  because  the  sun  is  more  powerful,  bujt  because  the  angle  of 
reflection  is  more  favorable.  It  is  generally  necessary  to  give  more  exposure  with  sun- 
shine and  a  clear  blue  sky  than  with  the  sun  shining  between  patches  of  white  sky,  as 
the  shadows  are  then  better  illuminated  and  contrasts  less  violent. — Read  before  the 
Philadelphia  Amateur  Photographic  Club. 


224         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

It  is  an  unquestionable  fact  that  the  most  brilliant  image  on  the  ground-glass 
is  produced  by  lenses  having  the  smallest  reflecting  surface  adapted  to  a  well- 
blackened  camera.  It  is  also  evident  that  when  all  the  rays  but  those  forming 
the  part  of  the  image  depicted  on  the  ground-glass  are  excluded  by  means  of  a 
hood  or  cone,  the  image  will  gain  in  vigor  and  brilliancy.  The  question 
whether  it  will  not,  in  certain  cases,  be  an  advantage  to  sacrifice  some  of  this 
brilliancy  for  the  sake  of  rapidity  of  action,  is  one  which  the  practical  photog- 
rapher is  called  upon  to  decide  promptly.  Happily  all  the  methods  of  accele- 
ration are  rendered  useless  now,  but* we  are  compelled  to  be  more  than  ever  on 
the  alert,  lest  overexposure  give  us  flat,  foggy,  insipid  results. 

100.  Suggestions  were  made  by  several  experimentalists  to  secure  similar 
advantages  by  chemical  means. 

Their  methods  have  a  bearing  on  present  manipulation,  also,  and  some  of 
them  are  therefore  added  to  the  notes. 

100.  Instead  of  using  spirits  of  wine,  use  wood  spirit  (methylic  alcohol).  Formula: 
Water,  300  grammes;  sulphate  of  iron  and  ammon.,  8  grammes;  glacial  acetic  acid,  15 
grammes ;  wood  spirit,  15  grammes.  The  strengthening  solution  is  prepared  as  follows : 
Water,  200  grammes;  pyrogallic  acid,  0.60  gramme;  citric  acid,  0.60  gramme;  wood 
spirit,  0.10  gramme. 

By  using  wood  spirit  instead  of  spirits  of  wine,  the  exposure,  under  the  same  circum- 
stances, of  43  and  58  seconds,  can  be  reduced  to  10,  8,  6,  arid  even  4  seconds.  I  attribute 
the  extraordinary  action  of  the  developer  to  the  circumstances  that  it  penetrates  the 
collodion  film,  while  the  developer  with  spirits  of  wine,  only  acts  on  the  surface. — G. 
NOELL. 

Have  a  solution  of  protosulphate  of  iron,  acetic  acid,  and  water,  which  has  been  heated 
to  100°,  in  a  closed  vessel  for  several  days.  By  adding  to  the  ordinary  iron  developer 
one-tenth  of  its  volume  of  the  above  developer,  it  will  be  found,  after  several  days,  to 
have  obtained  the  following  qualities: 

a.  Shortening  the  time  of  exposure  one-third. 

b.  The  developed  picture  is  more  intense. 

c.  The  developer  will  not  spoil  in  a  few  days  as  that  without  this  preparation  added, 
but  will  work  more  regular  the  older  it  gets,  without  fogging.     Moreover,  these  results 
change  according  to  the  condition  of  the  collodion,  and  principally  the  silver  bath.     It 
must  also  be  noticed  that  the  valuable  qualities  of  this  developer  show  themselves  on 
cloudy  days.     In  clear  weather  its  superiority  is  less  noticeable.     On  this  occasion  we 
will  mention  another  preparation  of  iron  which  is  sold  under  the  name  of  carbolate  of 
iron.    This  preparation  consists,  according  to  an  analysis  of  Dr.  Jul.  Schnauss,  of  proto- 
sulphate of  iron  and  carbolic  acid.     Whether  the  carbolic  acid  is  mixed  chemically  with 
the  iron,  or  is  only  a  mechanical  mixture,  could  not  be  ascertained  with  certainty.     Of 
course,  carbolic  acid  will  combine  with  metallic  oxides  to  form  crystallized  formations. 
It  will  reduce  for  itself  the  nitrate  of  silver,  and  its  addition  to  the  developer  is  theoreti- 
cally correct. — DR.  D.  VON  MONCKHOVEN. 


EXPOSURE,    OR    THE    QUESTION    OF    TIME.  225 

101.  While  an  overtimed  picture  is  to  be  deplored,  yet,  be  it  remembered, 
there  is  more  likelihood  of  such  au  one  being  "  saved  "  in  development  than 
there  is  of  an  underexposed  picture.     You  cannot  hope  to  bring  out  by  de- 
velopment beauties  and  qualities  which  you  have  not  allowed  to  be  started  into 
existence  by  sufficient  exposure. 

102.  Exposure  is  largely  a  matter  of  inspiration,  of  feeling.     There  is  no 
royal  road  to  its  proper  attainment.     You  must  learn  how,  just  as  you  must 
acquire  musical  excellence  or  master  a  language.     You  must  go  through  the 
experience  and  the  plate-spoiling  with  the  disappointments  incident  thereto. 
Then  it  will  come  to  you — to  stay. 

101.  Undertimed  photographs  are  to  be  seen  everywhere,  and  from  all  places,  nearly. 
It  seems  to  be  a  common  disease  among  photographers;  stopping  off  the  light  just  a  little 
too  soon,  thereby  spoiling  what  would  have  been  a  good  production.    Every  photographer 
should  examine  every  photograph  he  comes  across,  his  own  work  as  well  as  the  work  of 
others,  with  an  eye  of  inquiry ;  if  it  is  good,  find  the  cause  of  its  being  good ;  if  "  better," 
why  it  is  better ;  if  "  best,"  there  is  certainly  a  reason  for  its  being  so,  and  an  examina- 
tion by  an  experienced  eye  will  soon  determine  wherein  it  is  better,  and  why  it  is  better. 
Short  exposures  in  most  cases  produce  startling  effects.     As  a  general  thing,  however, 
there  is  a  lack  of  detail  which  nearly  ruins  the  work.     A  little  more  time  given  the 
exposure  would  have  produced  a  first-class  photograph.     On  the  other  hand,  too  long  an 
exposure  produces  a  flat,  low  tone,  worthless  print.     Too  much  or  too  little  are  equally 
bad,  but  the  failure  in  the  latter  is  much  more  frequent  than  in  the  former. — I.  B. 
WEBSTER. 

102.  No  rule  can  be  laid  down,  but  the  photographer  must  use  his  own  judgment  as  to 
the  position  of  the  sun  that  will  produce  a  good  picture.     It  may  be  almost  invariably 
accepted  that  the  sun  should  not  be  in  the  same  position  as  the  photographer;  that  is  to 
say,  with  its  rays  parallel  with  the  lens  and  camera.     In  landscapes-  a  side  light  is,  as  a 
rule,  to  be  chosen,  with  modifications  according  to  circumstances.     In  the  case  of  a  river 
with  trees  on  both  sides,  the  chief  care  is  to  expose  when  the  sun  is  in  such  a  position 
that  any  very  dark  patches  in  the  foliage  do  not  exist,  or  at  least  not  inharmoniously ; 
also,  that  the  shadows  from  the  trees  of  one  bank  of  the  river  do  not  darken  the  foliage 
of  the  other  bank  to  such  an  extent  as  to  rob  it  of  its  pleasingly  clear  definition.     Clear 
definition  must  not  be  confounded  with  hard  effects ;  most  beautifully  soft  and  yet  clear 
definition  with  atmospheric  effect  may,  and  should  be,  obtained  without  any  tendency  to 
hardness.     In  the  majority  of  cases  it  may  be  taken  as  positive  that  foliage  is  better  ren- 
dered without  the  aid  of  the  direct  rays  of  the  sun ;  in  cases  where  water  forms  part  of 
the  picture,  it  is  almost  always  so.     But  very  often  very  fine  and  most  desirable  effects 
may  be  produced  by  dividing  the  exposure,  giving  one  part  while  the  sun  is  shining  and 
another  with  diffused  light.     We  generally  find  that  the  lighted  or  partly  lighted  side  of 
a  landscape  is  taken,  and,  of  course,  in  a  large  number  of  instances  it  is  a  most  suitable 
proceeding;  but  there  are  sometimes  most  beautiful  exceptions  to  that  mode  of  pro- 
cedure, such  as  taking  a  view  with  the  shaded  side  of  the  picture  toward  the  camera. 

15 


226        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

When  to  expose  is  the  first  consideration. 

The  art  side  we  have  looked  at,  and  we  have  considered  the  lenses.  The 
light  side,  too,  we  understand.  All  these  in  order,  the  atmosphere  may  cast  a 
dozen  wily  influences  over  things  generally  that  will  hold  success  with  a  grip 
that  will  baffle  our  best  brains  to  unclasp. 

Then  the  inspiration  will  come  in,  and,  if  you  are  watchful  and  quick,  you 
will  come  out  the  victor. 

103.  How  to  expose  becomes  the  next  anxious  inquiry.  It  might  be 
answered  with  a  single  word — enough. 

The  time  of  exposure,  like  many  other  features  in  photography,  cannot  be  learned,  as 
can  a  process ;  it  requires  a  true  artistic  feeling  in  the  photographer,  strengthened  by 
experience. 

A  few  remarks  under  this  head  on  portraiture.  The  time  at  which  to  expose  is  a  point 
quite  as  important  in  portraiture  as  in  landscape  photography.  I  have  always  found 
that  it  is  a  good  thing  to  allow  the  sitters  some  time  to  look  at  specimens,  and  stroll 
about  the  studio  or  place  of  sitting,  as  that  allows  time  for  their  nerves,  heart,  and 
muscles  to  get  more  composed  after  their  walk  or  ride.  By  giving  them  a  number  of 
interesting  photographs  to  examine  while  you  prepare,  their  imaginations  and  tempera- 
ments get  generally  a  little  more  calmed,  and  the  chances  are  much  more  in  favor  of  a 
good  picture. — H.  A.  H.  DANIEL. 

103.  How  to  Expose.  For  views,  I  maintain  that  always,  if  practicable,  a  long  exposure 
and  weak  developer  give  far  the  best  results.  I  am  of  opinion  that  when  a  strong  devel- 
oper is  used  there  is  a  much  greater  likelihood  of  hardness,  and  as  a  strong  developer 
requires  a  quick  exposure,  I  do  not  think  that  such  detail  is  secured  as  with  a  long  expo- 
sure; that  is  to  say,  in  taking,  for  instance,  the  case  of  a  landscape  with  fairly  lighted 
parts,  and  also  very  dark  portions  in  the  depths  of  the  foliage,  presuming  a  short  exposure 
be  given  and  a  strong  developer  used,  I  believe  that  the  well-lighted  parts  assume  a  cer- 
tain degree  of  hardness,  and  the  dark  portions  of  foliage  do  not  contain  so  much  detail. 
But  suppose  we  use  a  weak  developer  and  give  a  long  exposure,  the  details  in  the  deep 
shadows  get  a  longer  time  for  impression  on  the  film,  and  can  be  brought  out  slowly  but 
surely  by  building  up  the  negative,  at  the  same  time  the  weakness  of  the  developer  pre- 
vents any  hardness  in  the  well-lighted  parts. 

In  making  exposures  there  is  one  thing  that  should  be  continually  studied.  It  is  to 
endeavor  to  gain  a  tolerably  accurate  idea  of  the  actinic  power  or  value  of  different  colors 
in  nature,  such  as  the  light  and  dark  greens,  browns,  grays,  yellows,  and  reds.  This  can 
only  be  acquired  by  carefully  noting  the  exposures  and  examining  afterwards  the  nega- 
tives, carrying  the  landscape  in  the  eye  as  well  as  possible.  By  so  doing  a  far  better  idea 
of  the  required  length  of  exposure  is  obtained  than  by  any  other  method  I  am  acquainted 
with.  We  cannot  rely  on  apparently  equally  lighted  subjects,  or  recollecting  the  expo- 
sure of  one  subject  and  applying  it  to  another.  What  appear  to  be  equally  lighted 
subjects  are  very  often  not  so.  By  making  this  a  little  point  of  study  many  a  negative 
will  be  saved  from  under-  or  over-exposure. — H.  A.  H.  DANIEL. 


EXPOSURE,   OR    THE    QUESTION    OF    TIME.  227 

I  have  already  hinted  at  my  belief,  that  a  long  exposure  is  preferable — i.  e.f 
relatively  long.  It  is  my  habit  not  to  employ  "  lightning/'  nor  very  quick 
plates,  if  my  subject  will  permit  me  to  use  slower  ones. 

Neither  do  I  think  it  a  good  plan  to  use  quick  plates  with  a  very  small 
diaphragm  for  ordinary  subjects. 

104.  Quick  plates  are  a  splendid  reserve  power,  but  they  were  never  intended 
for  general  use. 

104.  For  landscape  work,  pure  and  simple,  where  an  instantaneous  exposure  is  not 
required,  I  believe,  and  always  advise,  that  a  slow  plate  of  fourteen  to  sixteen  degrees 
Warnerke  will  give  better  and  more  satisfactory  results  than  a  very  rapid  plate,  and  for 
the  following  reasons :  A  slow  plate  gives  great  contrast  and  a  brilliant  image,  while  a 
rapid  plate  gives  a  soft  effect  and  a  certain  flatness,  which  are  not  easily  overcome.  In 
portraiture,  where  hard  contrasts  should  be  avoided,  these  rapid  plates  are  very  suitable. 
The  brilliancy  and  intensity  in  a  slow  plate  are,  of  course,  largely  due  to  the  inherent 
chemical  quality  of  the  emulsion. 

Again,  more  latitude  is  allowable  both  in  exposure  and  development  with  a  slow  plate. 
A  photographer  may  be  perfectly  acquainted  with  the  capabilities  of  his  plate  and  lens, 
and  on  ordinary  subjects  will  hit  pretty  nearly  the  right  exposure  nine  out  of  ten  times. 
But  the  image  on  the  ground-glass  is  deceptive,  and  there  is  an  endless  variety  of  subjects 
where  the  most  expert  photographer  is  puzzled,  and  hardly  knows  what  exposure  to  give. 
For  example,  dimly  lit  landscape  under  trees ;  autumn  foliage  with  non-actinic  red,  yel- 
low, brown,  and  dark  green  leaves ;  heavy  black  foregrounds  with  well-lit  distances,  need 
all  the  latitude  possible,  and  here  is  where  the  ad  vantage  of  the  slow  plate  comes  in.  In 
doubtful  cases,  like  those  mentioned,  a  very  full  exposure  may  be  given,  and  five  or  even 
ten  seconds  too  much  will  not  prevent  a  good  negative  from  being  obtained,  while  with 
a  rapid  plate  a  difference  of  two  or  three  seconds  may  ruin  the  resulting  negative,  for  it 
is  almost  impossible  to  get  anything  but  a  flat  picture  on  an  overexposed  rapid  plate. 

It  may  be  suggested  that  by  using  a  small  diaphragm  the  same  latitude  of  exposure 
may  be  obtained  with  a  rapid  plate  as  with  a  slow  one.  This  may  be  so  to  a  limited 
extent,  but  working  a  very  small  diaphragm  lessens  the  atmospheric  effect  and  gives  a 
certain  flatness  and  lack  of  brilliancy.  Diaphragms  ought  not  to  be  used  as  a  means  to 
lessen  the  light,  but  only  to  get  a  sfyarp  picture  all  over  the  plate ;  the  largest  diaphragm 
that  will  effect  this  is  the  right  one  to  use,  a  smaller  one  will  give  only  monotone  pictures 
without  any  advantage. 

Then,  again,  in  development  a  slow  plate  will  stand  more  variation  and  rougher  treat- 
ment without  fogging.  It  is  easier  restrained,  and  can  be  forced,  without  losing  its 
printing  qualities,  to  an  extent  which  would  be  total  ruin  to  a  rapid  plate.  The  greater 
intensity  of  a  slow  plate  allows  one  to  use  a  very  dilute  developer,  thus  keeping  the  plate 
under  perfect  control,  and  saving  many  negatives  that  would  otherwise  be  lost  through 
overexposure,  but  with  a  rapid  plate  no  such  treatment  is  allowable,  and  overexposure 
cannot  be  corrected  by  diluting  the  developer,  as  the  resulting  image  will  be  flat  and 
thin,  and  worthless  for  printing  without  intensification.  Such  a  plate  can  only  be  saved 


228        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  doctors  agree  ou  this  point,  therefore  I  need  only  refer  to  their  notes, 
rather  than  expatiate  myself. 

105.  What  light  gives  us  the  best  effects  ?  is  another  common  query.  The 
answer  is — sunlight.  I  do  not  mean  a  blue  sky,  for  we  all  know  that  we  do 

by  the  addition  of  plenty  of  bromide  from  the  very  beginning,  and  even  then  it  is  neces- 
sary to  vary  the  component  parts  of  the  developer  so  often  that  the  whole  operation 
becomes  perplexing  and  uncertain. 

My  advice,  therefore,  is,  use  a  slow  plate  for  landscape  work,  give  generous  exposure, 
and  dilute  your  developer. — DR.  S.  C.  PASSAVANT. 

It  is  a  fact  that  the  great  sensitiveness  of  dry  plates  facilitates  in  an  extraordinary 
manner,  the  taking  of  instantaneous  pictures,  and  that  there  are  even  cases  when  it  seems 
impossible  to  give  short  enough  exposure. 

Dr.  Neuhaus,  who  has  recently  returned  from  the  Sandwich  Islands  with  a  number  of 
remarkable  pictures,  declares,  that  he  found  it  necessary  to  make  use  of  a  Steinheil 
wide-angle  lens  with  the  smallest  stop — that  is,  the  smallest  opening  which  can  practi- 
cally be  used  in  operating  upon  open,  sunlit  landscapes.  All  views  not  so  taken  with 
the  instantaneous  shutter,  showed  themselves  over-exposed,  so  brilliant  is  the  light  in 
that  region.  But  it  does  not  follow  that  we  should  always  use  for  instantaneous  work 
and  under  every  circumstance  a  wide-angle  lens  with  smallest  stop.  What  would  do 
well  enough  for  open  landscape  will  not  serve  in  shady  forests,  or  narrow  places,  or  rocky 
cavities  where  the  light  of  the  broad  sky  is  only  filtered,  as  it  were,  through  small  open- 
ings, and  what  is  possible  in  the  broad  light  of  noon  is  not  possible  when  the  sun  is 
declining  or  when  the  sky  is  overcast  with  clouds.  Finally,  a  point  of  great  importance 
is  the  distance  of  the  passing  object  from  the  camera;  the  manner  of  its  passage,  and  its 
position,  whether  perpendicular  to  or  nearly  in  the  direction  of  the  camera. 

Every  professional  of  experience  is  well  aware  that  an  express  train  which  impresses 
itself  upon  the  field  of  vision  with  a  velocity  of  thirty  feet  with  an  objective  of  six  inch 
focus  at  a  distance  of  twenty  paces,  and  which  lasts  for  one- twentieth  of  a  second,  makes 
a  motion  of  one-twenty-seventh  of  an  inch  upon  the  plate;  that  is,  almost  a  half  line, 
which  will  give  the  impression  of  a  blur.  At  double  that  distance,  forty  paces,  the  blurring 
is  only  half  as  much ;  at  three  times,  one-third;  and  much  less  when  the  direction  of  mo- 
tion is  oblique  to  the  axis  of  vision.  Such  facts  are  usually  overlooked  by  the  amateur. 

Photography  is  at  present  an  easy  thing,  but  a  certain  amount  of  mother  wit  is  neces- 
sary when  we  expect  to  succeed  with  difficult  subjects. — DR.  H.  W.  VOGEL. 

105.  I  will  ask  this  question :  How  many  pictures,  amongst  the  thousands  painted  by 
first-rate  men  and  authorities  in  the  artistic  world,  representing  daylight  scenes,  have 
been  painted  without  sunlight  represented  as  shining  on  some  portion  or  other  of  the 
work?  Unless  for  some  very  exceptional  effects,  I  am  inclined  to  think  sunshine  is 
always  a  factor  in  the  arrangement.  I  cannot  call  to  mind  a  single  instance  of  a  leading 
landscape  painting  quite  destitute  of  sunshine.  Take  a  stroll  through  our  picture 
galleries — South  Kensington,  for  instance — and  try  to  find  a  daylight  landscape  without 
sunshine  effects.  The  search  will,  I  think,  be  tedious  and  unremunerative  in  this 
respect ;  yet  there  are  representative  pictures  of  most  of  our  leading  artists  to  select  from. 


EXPOSURE,    OR    THE    QUESTION    OF    TIME.  229 

not  always  get  the  best  effects  under  such.  The  most  aggravating  sky  to  work 
under  is  a  cloudy  one,  when  the  white-winged  messengers  are  having  a  gala 
day  and  shifting  about,  changing  the  light  every  few  seconds.  But  on  such 
gala  days  we  may  get  our  richest  effects  if  we  but  have  the  patience  to  watch 
and  wait.  But  such  rare  days  do  not  come  always  when  wanted. 

106.  The  shady  day,  however,  is  to  be  avoided.     Pictures  can  be  made  on 

« 

If,  then,  sunshine  be  unnecessary  for  pictorial  effects,  how  is  it  that  it  is  always  adopted? 
and  why  are  not  paintings  made  to  represent  nature  under  a  leaden  sky,  or,  at  least, 
where  sunshine  is  absent,  in  preference  ? 

In  answer,  the  photographic  advocates  of  no  sunshine  may  say  that  the  greater  play 
of  color  in  sunlight  is  the  inducement  to  painters ;  but,  as  color  effect  is  to  be  ignored  as 
much  as  possible  by  the  photographer,  the  less  there  is  of  it  the  better  for  perfect  pho- 
tographic results.  But  sunshine  does  something  else  besides  vary  color  effects  ;  it  quite 
as  much  varies  form  and  composition.  A  bright  gleam  of  sunshine  will  frequently  make 
a  beautiful  picture  out  of  what  was  without  it  a  flat,  uninteresting  subject. 

Brilliancy  in  a  photograph  is  a  mere  matter  of  intensity  altogether  irrespective  of  any 
artistic  consideration.  It  alters  neither  form  nor  composition ;  but  sunshine  not  only 
supplies  this  intensity,  but  especially  improves  the  picture  by  varying  the  forms.  In 
illustration  of  this,  take  a  foreground  with  nothing  but  a  grass  bank  and  short  herbage 
growing  upon  it :  the  advocates  of  no  sunlight  represent  it  as  a  blank  and  even  patch, 
which  it  possibly  may  be ;  but,  give  sunshine  a  chance,  and  the  shadows  of  neighboring 
trees,  etc.,  or  inequalities  in  a  ground  itself,  make  a  broken  and  pleasant  effect  without 
an  accessory  of  any  kind. 

What  applies  here  to  the  small  piece  of  foreground  holds  good  with  the  whole  of  the 
landscape ;  and  I  firmly  believe  that  no  landscape  was  ever  taken  on  a  sunless  day,  no 
matter  how  successfully,  but  would  with  the  same  skill  of  manipulation  have  been 
infinitely  better  done  on  a  sunny  one.  In  fact,  it  is  a  mystery  to  me  how  anyone  who 
has  intelligently  studied  landscape  effect  at  all  could  think  otherwise.  Because  there  is 
sunlight  there  is  no  necessity  for  chalkiness  or  snowy  effect  in  the  foliage  or  want  of 
detail  in  the  shadows.  These  effects  are  mere  errors  of  manipulation,  and  chiefly  occur 
when  the  plate  has  had  insufficient  exposure  or  faulty  development,  and  are  not  due  to 
the  lighting  of  the  subject. — EDWARD  DUNMORE. 

106.  These  remarks,  of  course,  are  intended  to  apply  to  general  landscape  work. 
Special  instances  do  undoubtedly  occur  now  and  again  where  the  absence  of  sunshine  is 
advantageous.  When,  for  instance,  from  the  exigencies  of  the  situation,  one  is  obliged 
to  work  with  the  sun  directly  in  front,  then  there  is  no  doubt  of  the  advantage  of  cloudy 
weather;  but,  from  an  artistic  standpoint,  such  subjects  would  not  be  photographed  at 
all.  Still,  as  they  have  to  be  done  occasionally,  the  least  objectionable  conditions  are, 
of  course,  selected ,  but  this  only  proves  the  exception. 

In  architectural  subjects — say  some  building  in  its  entirety — when  the  position  of  the 
camera  is  entirely  under  the  control  of  the  artist,  a  satisfactory  picture  could  not  be  made 
without  sunlight.  Architects  themselves  carefully  consider  the  effect  of  cast  shadows  on 


230         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

such  days,  it  is  very  true,  but  their  quality  is  inferior ;  the  results  are  flat, 
shadowless,  void  of  snap,  brilliancy,  and  vim. 

107.  Another  influence  upon  the  exposure  comes  from  the  lens  or  objective 
used.  It  has  already  been  hinted  at,  and  is  one  that  should  be  considered  at 
all  times.  Enough  instruction,  surely,  has  been  given  to  render  anything  more 

their  works  as  a  means  of  enhancing  the  appearance  of  the  structure,  and  giving  relief 
and  prominence  to  some  ornamental  or  architectural  feature.  The  even- light  photog- 
rapher, trusting  to  intensification,  would  make  but  a  poor  hand  of  such  a  subject.  It  is 
true  little  bits  of  detail  may  occasionally  be  rendered  better  without  direct  sunshine  fall- 
ing upon  them ;  this  has,  however,  nothing  to  do  with  landscape  work,  and  comes  under 
an  entirely  different  set  of  conditions.  Again :  most  works  giving  instruction  in  drawing 
and  painting  go  deeply  into  the  matter  of  shadows  and  their  perspective  and  of  chiaros- 
curo generally.  What  would  be  the  use  of  all  this  knowledge  if  effects  were  better  without 
direct  sunlight?  No;  depend  upon  it,  sunlight  in  landscape  work  is  as  absolutely 
necessary  to  perfect  pictorial  results  as  the  reducing  agent  is  in  the  development  of  the 
photographic  image. — EDWARD  DUNMOEE. 

107.  President  Barnard  says :  "  Before  attempting  to  construct  a  formula  which  should 
express  the  relation  of  intensity  of  light  to  the  duration  of  exposure  required  to  produce 
a  definite  amount  of  chemical  change,  we  should  require  to  know  more  than  we  do  about 
the  laws  which  govern  chemical  changes  during  their  progress,  for  the  law  which  you 
find  to  fail  takes  it  for  granted  that  the  resistance  to  change  opposed  by  a  chemical 
compound  to  the  action  of  light  is  uniform  from  beginning  to  end — a  thing  which  we 
have  no  right  to  affirm.  I  know  of  no  better  means  of  determining  this  relation  between 
area  of  lens  and  the  proper  duration  of  exposure  than  careful  experiments,  systematically 
conducted  with  lenses  of  various  areas,  and  with  similar  illumination  throughout.  An 
empirical  law  might  thus  be  ascertained,  which  for  practical  purposes  would  answer 
quite  as  well  as  a  theoretical  formula  mathematically  expressed." 

The  laws  governing  the  rapidity  of  the  lens,  neglecting  its  color  and  the  number  of  its 
reflecting  surfaces,  are :  First.  The  relative  rapidity  of  two  lenses  having  the  same  aper- 
tures is  inversely  as  the  square  of  their  equivalent  foci.  Second.  The  relative  rapidity 
of  two  lenses  having  the  same  equivalent  foci  is  nearly  as  the  areas  of  their  apertures. 

For  example,  take  two  lenses  having  the  same  sized  aperture,  one  having  an  equiva- 
lent focus  of  twelve  inches,  and  the  other  of  six  inches;  the  lens  with  the  six-inch  focus 
will  be  four  times  as  rapid  as  the  other.  Or  of  two  lenses  having  the  same  equivalent 
foci,  one  with  an  aperture  two  inches  in  diameter,  and  the  other  with  an  aperture  of  one 
inch ;  the  two-inch  lens  will  be  approximately  four  times  as  fast  as  the  other. 

The  Photographic  Society  of  Great  Britain,  in  order  to  overcome  the  great  confusion 
arising  from  the  different  systems,  or  rather  lack  of  systems,  used  by  different  opticians 
in  numbering  their  stops,  have  adopted  a  "universal  system,"  based  upon  the  ratio 
between  their  diameters  and  the  equivalent  focal  length  of  the  lenses  with  which  they 
are  used.  As  the  basis  of  their  system,  they  have  taken  a  portrait  lens  the  diameter  of 
whose  aperture  is  one-fourth  its  equivalent  focal  length,  calling  that  stop  or  aperture 


EXPOSURE,    OR    THE    QUESTION    OF    TIME.  231 

than  a  reference  to  the  few  notes  below  unnecessary  on  this  topic,  especially 
when  read  with  the  offerings  concerning  lenses  and  diaphragms. 

108.   A  great  deal  of  guesswork   is  spared  the  beginner  by  the    modern 

No.  1 ;  stop  No.  2  is  one  of  half  the  area,  and,  therefore,  requires  approximately  twice 
the  exposure.  In  this  "  universal  system  "  the  number  of  stop  represents  the  number  of 
seconds  exposure  required  by  the  stop,  when  stop  No.  1  requires  an  exposure  of  one 
second. 

I  think  a  modification  of  this  system  would  be  of  the  greatest  possible  advantage  to 
amateurs  in  enabling  them  to  express  the  duration  of  exposure  in  terms  which  are 
common  to  all  lenses. — C.  W.  DEAN. 

108.  The  usual  method  adopted  for  the  measurement  of  the  speed  of  photographic 
drop-shutters,  depends  on  photographing  a  white  clock-hand  revolving  rapidly  in  front 
of  a  black  face.  The  chief  difficulty  in  the  case  is  to  maintain  a  uniform  rotation  at  high 
speed.  To  avoid  this  difficulty,  and  to  determine  the  uniformity  of  exposure  of  any 
particular  shutter  under  apparently  like  circumstances,  the  following  method  has  been 
suggested.  In  carrying  out  the  experiment  in  practice,  I  have  had  the  assistance  of 
Mr.  J.  0.  Ellinger. 

A  tuning-fork,  B  (Fig.  233),  with  a  mirror  attached  to  the  side  of  one  of  the  prongs,  is 
placed  in  front  of  the  camera-lens.     This  mirror  is  so  arranged  as  to  reflect  into  the 
camera,  (7,  a  horizontal  beam  of  sun- 
light, which,  before  reaching  the  fork,       •  FIG.  233. 
has    passed  through   a  hole    in    the 
screen,  S,  placed  about  ten  feet  dis- 
tant.    This  produces  on  the  ground  - 
glass  a  minute  brilliant  point  of  light. 
If  the  fork  be  set  vibrating,  the  point 
will  become  a  short,  fine   horizontal 
line ;  if  the  fork  be  rotated  about  its 

longitudinal  axis,  the  line  will  become  a  sinusoidal  curve  described  on  the  circumference 
of  a  circle  of  long  radius.  A  photographic  plate  is  now  inserted  and  the  drop-shutter 
attached.  On  releasing  the  latter,  it  will  be  found  that  a  portion  of  the  sinusoid  has 
been  photographed,  and  the  precise  exposure  may  be  determined  by  counting  the  number 
of  vibrations  represented  on  the  plate. 

The  mirror  employed  should  be  somewhat  larger  than  the  lens  to  be  measured,  so  as 
to  cover  its  edges  during  the  whole  exposure.  The  mirror  may  be  glued  directly  to  the 
prong  of  the  fork  with  strong  carpenter's  glue,  after  first  scraping  off  a  little  of  the 
silvering  at  the  edges  of  the  glass.  The  rate  of  the  fork  is  then  determined,  by  com- 
parison with  a  standard  fork,  by  the  method  of  beats.— W.  H.  PICKERING. 

Measuring  the  Time  of  Exposure.  First  Method. — The  diapason  as  an  instrument  for 
measuring  time  is  the  only  one  that  has  an  indisputable  value ;  and  we  believe  that, 
instead 'of  leaving  it  to  scientists,  we  should,  on  the  contrary,  utilize  it  in  the  interest  of 
our  investigations.  The  objection  may  be  urged  that  the  divers  methods  that  we  describe 
are  not  within  the  reach  of  all.  This  is  not  to  be  denied.  But  it  seems  to  us,  if  we  are 


232 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


exposing  shutter.  With  the  pneumatic  holder  ill  his  hand  he  may  learn  to 
spell  out  the  riddle  tolerably,  and  gradually  grow  up  to  the  mastery.  Or,  he 

to  measure  hundredths  or  thousandths  of  seconds,  instruments  of  high  precision  are 
indispensable.  To  measure  by  approximation  such  small  fractions  of  seconds  seems  to 
us  as  foolish  as  to  weigh  milligrammes  with  gramme  weights.  If  we  take  up  these  ques- 
tions it  is  necessary  to  do  so  with  all  possible  precision,  and  it  is  to  carry  out  this  order 
of  ideas  that  I  have  devised  the  following  method. 

Take  a  registering  cylinder  put  in  motion  by  a  Foucault  regulator ;  on  its  edge  affix  a 
brilliant  point — the  head  of  a  nickel-plated  nail,  for  example.  The  point  is  carried 
forward  by  the  regulator  at  the  same  time  as  the  cylinder  of  which  it  forms  a  part ;  it  is 
its  displacement  that  we  will  photograph.  It  moves  behind  a  graduated  dial-plate 
pierced  with  a  circular  opening  (Fig.  234).  The  dial  is  black ;  the  divisions  are  white 

FIG.  234. 


Dial  Method.    A,  brilliant  point. 


The  cylinder  is  covered  with  a  smoked  paper,  upon  which  vibrates  an  electric  diapason 
furnished  with  a  small  style.  A  camera  is  now  directed  toward  the  dial,  the  regulator 
is  put  in  motion,  the  style  is  made  to  touch  the  diapason,  and  the  stop  is  lifted. 


EXPOSURE,   OR    THE    QUESTION    OF    TIME.  233 

may  use  a  photometer  or  sensitometer  to  determine  the  sensibility  of  his  plates, 
and  expose  according  to  what  they  indicate. 

We  give  here  the  reproduction  of  the  result  of  an  experiment.  We  see  the  divided 
dial  and  the  track  A  B  left  by  the  point.  Light  commenced  to  act  at  A  and  finished  at 
B.  We  have  now  to  see  on  our  sinusoid  to  what  places  these  two  points  correspond, 
and  what  time  has  elapsed  between  A  and  B ;  nothing  is  more  simple.  With  the  hand 
the  cylinder  is  made  to  revolve  until  the  brilliant  point  reaches  A.  This  is  the  com- 
mencement of  our  impression,  and  we  now  draw  a  line  which  cuts  our  sinusoid,  dis- 
placing our  diapason  on  the  parallel  stand.  The  point  A  corresponds  to  the  point  of 
intersection  of  that  line  and  of  the  sinusoid.  We  continue  the  march  of  the  cylinder 
until  the  point  reaches  B.  We  draw  another  line,  which  gives  us  the  point  B.  All  we 
have  to  do  now  is  to  count  the  number  of  vibrations  comprised  between  A  and  B  to 
ascertain  how  long  the  light  has  acted  and  discover  the  time  of  our  exposure.  In  this 
experiment  we  have  ten  vibrations;  as  the  diapason  gives  250  vibrations  in  a  second,  the 
time  of  exposure  is,  therefore,  •££$,  that  is  to  say,  ^th  of  a  second. 

By  adopting  this  method,  combined  with  optical  and  graphical  methods,  it  is  no  longer 
necessary  to  have  a  regular  motor,  since  we  know  at  every  moment  the  law  of  motion  of 
the  registering  cylinder.  There  is  no  necessity  to  .have  the  dial  divided  with  precision, 
inasmuch  as  its  graduation  only  serves  to  give  points  of  comparison.  The  method  then 
becomes  much  more  simple,  whilst  at  the  same  time  it  gives  results  that  are  of  absolute 
precision. — ALBERT  LONDE. 

It  requires  but  little  practice  to  be  able  to  measure  off  a  minute  without  varying  more 
than  a  second,  and  in  that  case  both  stop-watch  and  the  device  I  am  going  to  recommend 
may  be  dispensed  with  entirely,  though  a  novice  is  liable  to  become  disconcerted  by  any 
sudden  excitement.  I  therefore  suggest  the  use  of  a  time-ball,  which  consists  of  a  half- 
inch  bullet  firmly  attached  to  a  cord  twelve  inches  long,  in  which  a  knot  is  made  just 
nine  and  three-quarter  inches  from  the  centre  of  the  bullet.  Swing  the  ball,  not  vio- 
lently, holding  the  cord  at  the  knot,  and  the  intervals  will  be  exact  half-seconds,  though 
for  seconds  every  other  beat  only  should  be  counted.  This  principle  is  based  on  the  fact 
that  the  length  of  a  pendulum,  beating  seconds,  measures  39.37  inches,  which  is  a  metre, 
the  French  standard  of  linear  measure.  If  one  wishes,  however,  to  be  quite  certain  in 
determining  the  amount  of  exposure,  one  should  not  permit  the  common  mistake  of  sac- 
rificing one  count,  which  is  done  by  calling  the  removal  of  the  cap  "  one,"  and  for  twelve 
seconds  replacing  it  at  "  twelve."  That  is  but  eleven  seconds,  twelve  seconds  being  from 
one  to  thirteen. — WILFRED  A.  FRENCH. 

To  Determine  the  Relative  Sensibility  of  Sensitive  Films. — It  is  indispensable,  if  we  wish 
to  work  with  precision,  to  have  at  our  command  a  method  for  ascertaining  the  sensibility 
of  the  films  which  we  use.  This  sensibility  varies  according  to  the  emulsions  used,  and 
it  is  necessary  to  vary  the  time  of  exposure,  all  other  things  being  equal,  in  accordance 
with  their  sensibility.  The  method  most  generally  employed  is  that  depending  upon 
the  use  of  the  sensitometer  of  M.  Warnerke  (Fig.  234),  which  is  already  very  popular 
and  the  only  one  that  can  be  purchased.  Its  graduation  is  known,  and  when  we  are  told 
that  an  emulsion  gives  a  certain  degree  of  the  Warnerke  sensitometer,  we  know  what 


234 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  235. 


ETALON 


The  whole  subject  is  an  interesting  and  vital  one,  and  requires  careful 
attention.  At  first,  any  way,  "  go  slow." 

that  means  as  well  as  if  we  should  learn  that  the  thermometer  indicated  a  specified 
degree. 

When  it  is  necessary  to  ascertain  the  sensibility  of  papers  and  pellicles  nothing  is  easier 
than  to  cut  suitable  pieces  and  place  them  in  the  sensitometer,  a  species  of  pressure 

frame  for  whose  plate  is  substituted  a  translu- 
cent graduated  scale  divided  into  twenty-five 
degrees. 

The  interior  of  this  frame  measures  but  about 
8  x  10  centimetres,  and  can  therefore  contain 
but  fragments  of  plates,  even  the  quarter-plate 
which  measures  9x12  centimetres  could  not  be 
used.  It  becomes  therefore  necessary  to  cut 
with  a  diamond  the  emulsion  plate  to  make  the 
sensitometric  trial;  this  is  objectionable,  as  a 
whole  plate  must  be  destroyed  to  obtain  a  simple 
fragment  6x7,  surface  of  the  graduated  scale, 
and  if  the  trial  is  made  with  several  different 
preparations  it  carries  with  it  necessarily  the 
loss  of  several  plates.  To  this  objection  we  see 
but  one  remedy,  it  is  to  add,  in  all  the  bundles 
and  boxes  of  sensitive  plates  a  fragment  of  plate 
6x6  at  a  minimum,  to  be  used  in  making  the 
trial,  say  one-sixth  of  the  plate  13  x  18.  This 
useful  complement  would  not  cost  the  manu- 
facturers much  and  would  prove  of  great  ser- 
vice. To  sell  separately  sensitometric  plates 
would  not  lead  to  the  desired  end.  In  any  event 
it  would  be  better  to  indicate  upon  each  box 
the  sensitometric  degree  of  the  sensibility  of  the  plates,  but  to  verify  this  may  sometimes 
be  necessary,  and  for  this  reason  the  addition  of  a  sensitometric  plate  would  prove  very 
useful  to  all  amateurs  desirous  of  operating  with  precision.  We  submit  this  advice  to 
the  appreciation  of  the  manufacturers  of  plates  and  sensitive  pellicles. 

The  description  of  the  Warnerke  sensitometer  is  not  necessary  here,  as  the  manner  of 
using  it  accompanies  the  appliance.  We  may  add,  however,  that  it  is  convenient  to  use 
a  method  of  reading  the  degree  which  removes  all  doubt.  Now  here  is  what  happens : 
After  the  development  of  a  plate  impressioned  in  the  sensitometer,  we  often  see  a  series 
of  tints  having  about  the  same  value,  and  it  is  somewhat  embarrassing  to  determine  to 
what  degree  they  belong.  This  embarrassment  will  no  longer  exist  if  we  use  a  finder 
consisting  simply  of  a  piece  of  paper  of  a  normal  tint  pierced  with  an  opening  in  the 
centre ;  it  is  only  necessary  to  find  the  tint  which,  placed  under  the  opening,  is  more 
nearly  assimilated  to  the  ambient  natural  tint.  Mr.  Warnerke  has  adopted  as  the  normal 


EXPOSURE,    OR    THE    QUESTION    OF    TIME.  235 

After  considerable  experience  one  will  learn  to  judge  very  correctly  all  that 
involves  the  time  of  exposure,  and  become  more  and  more  expert.  Further- 
tint  that  of  No.  3  of  his  sensitometer.  Any  one  may,  without  difficulty,  prepare  this 
little  complement  to  the  instrument.  It  suffices,  with  a  little  India  ink,  diluted  with  a 
great  deal  of  water,  to  produce  a  uniform  tint  of  the  value  of  No.  3  seen  by  transparency, 
and  to  make  a  round  or  square  hole  in  the  centre.  The  sensitometric  print,  after  devel- 
opment, washed  and  not  fixed,  is  covered  successively  over  the  last  visible  numbers, 
stopping  at  the  one  the  tone  of  which  is  nearer  the  normal  tint.  Why  should  not  Mr. 
Warnerke  complete  his  charming  instrument  by  the  addition  of  a  finder?  He  has  doubt- 
less done  so,  and  if  he  has  not  done  so,  he  will. — LEON  VIDAL. 

Among  the  various  new  forms  of  apparatus,  which  become  more  necessary  than 
formerly  with  the  introduction  of  the  highly  sensitive  dry-plates,  there  are  the  so-called 
' '  sensitometers."  One  of  the  best  known  is  that  by  Warnerke,  which  consists  of  a  semi- 
transparent  scale  of  figures  made  by  the  Woodbury  process — the  transparency  of  the 
scale  decreasing  by  regular  degrees  from  1  to  24.  Under  this  scale  the  plate  to  be  tested 
is  exposed  a  certain  time.  The  manner  of  exposing  is  remarkable.  Warnerke  employs 
for  it  a  normal  light— that  is,  a  glass  pane- coated  with  phosphorescent  paint.  Before 
the  same  two  and  a  half  centimetres  of  magnesium  wire  are  burned,  then  the  whole  is 
left  undisturbed  a  minute,  when  it  is  placed  upon  the  scale  under  which  the  dry  plate 
lies.  Warnerke  states  that  the  light  obtained  thus  is  always  uniform.  I  did  not  find 
this  to  be  so,  however,  as  the  temperature  acts  in  such  a  way  upon  the  power  of  phos- 
phorescence of  this  paint  that  totally  diiferent  results  may  be  brought  about.  So,  for 
instance,  I  obtained  with  a  warmed  phosphorescence-plate  upon  an  emulsion-plate  the 
number  20 ;  in  the  cold,  however,  only  the  number  19,  making  a  difference  of  25  per 
cent.  The  mere  warmth  of  the  hand  increases  the  power  of  phosphorescence.  It  is 
further  to  be  objected,  that  it  is  not  possible  to  detect  small  degrees  of  differences  of 
sensitiveness  with  the  instrument;  the  smallest  measurable  difference  is  1 :  1£ — i.  e.,  3 : 4; 
but  among  dry  plates  of  different  kinds,  differences  of  sensitiveness  like  8  : 11  or  4  :  5,  not 
rarely  exist,  and  these  cannot  be  measured  accurately  with  the  instrument  in  question. 
Furthermore,  the  yellow  color  of  the  scale  is  a  drawback,  for  it  modifies  materially  the 
quality  of  the  light,  as  the  blue  rays  are  partly  absorbed.  For  these  reasons,  I  have 
constructed  another  sensitometer,  after  an  idea  published  at  least  thirteen  years  ago  by 
A.  Taylor.  The  scale  of  this  photometer  is  formed  by  a  metal  plate  with  holes.  This 
plate  covers  a  wooden  block  in  which  twenty-four  cylindrical  cells  are  drilled.  Above 
the  first  cell  one  hole  is  made,  above  the  second  two,  above  the  third  three,  and  so  on. 
Under  these  cells,  the  plate  to  be  tested  is  exposed  in  a  dark,  slide-like  contrivance,  and 
it  is  obvious  that  the  relative  clearness  under  the  different  cells  must  be  in  exact  propor- 
tion to  the  number  of  apertures  made  over  the  respective  cells.  When,  therefore,  two 
plates  are  exposed  equally  long  under  this  instrument  before  an  object  uniformly  illumi- 
nated, and  then  developed,  it  may  be  that  one  plate  will  show  the  effect  of  light  up  to 
cell  number  two  (with  two  holes),  and  the  other  up  to  cell  number  four  (with  four  holes). 
With  half  the  strength  of  light  the  same  result  was  obtained  with  the  first  plate  as  with 
the  whole  strength  in  the  second  plate,  and  the  first  plate  is,  therefore,  shown  to  be  twice 
as  sensitive  as  the  second. 


236         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

more  one  will  very  soon  learn  how  to  correct  any  errors  or  miscalculations  in 
exposure  by  means  of  the  dark-room  manipulations. 

In  order  to  clearly  indicate  how  far  the  effect  of  light  has  progressed,  a  thin  tin  is 
fixed  under  the  cells,  in  which  figures  are  cut  out  to  indicate  the  number  of  the  holes 
made  above.  For  exposing,  I  use  a  sheet  of  white  photographic  plain  paper,  which  is 
drawn  upon  a  board,  Bt  Fig.  236,  which  board  is  exactly  one  metre  distant  from  the 
photometer,  and  which  is  lighted  by  a  small  window,  about  twenty  feet  distant,  facing 
directly  the  sky,  or  through  an  aperture  in  the  studio  protected  with  screens.  As  the 

FIG.  236.  FIG.  237. 


strength  of  light  of  the  daylight  is  very  variable,  even  during  the  time  of  exposing  of  two 
plates,  I  use  a  double  instrument,  as  shown  in  Fig.  237,  and  in  which  the  two  plates  can 
be  exposed  simultaneously.  Of  course,  the  plates  are  also  developed  simultaneously  and 
equally  long.  The  temperature  of  the  developer  is  of  special  importance.  With  a  warm 
developer  often  three  or  four  figures  more  are  reached  than  with  a  cold  one,  and  it  is 
therefore  necessary  to  keep  the  developer  as  nearly  as  possible  at  the  same  temperature 
(66°  Fahr.),  which  can  be  done  by  using  ice  in  summer  and  warm  water  in  winter.  Of 
course,  this  must  be  done  only  when  it  is  intended  to  compare  the  results  of  summer 
experiments  with  the  results  of  experiments  made  in  winter.  If  the  two  plates  are 
exposed  simultaneously,  and  also  developed  at  the  same  time  with  the  same  developer, 
the  temperature  does  not  modify  the  results. — DE.  H.  W.  VOGEL. 

For  some  time  after  the  modern  gelatino-bromide  dry  plate  came  into  general  use,  it 
was  customary  to  describe  the  relative  degrees  of  sensitiveness  as  so  many  times  that  of 
wet  collodion ;  but  as  this  standard  varied  in  the  hands  of  every  operator,  something 
more  reliable  was  felt  to  be  a  desideratum.  To  meet  this  demand,  Mr.  Warnerke,  of 
London,  England,  introduced  the  instrument  to  which  his  name  has  been  given,  and, 
notwithstanding  its  many  faults,  it  is  the  only  one  that  has  received  even  a  limited  share 
of  public  notice,  or  been  in  any  degree  considered  authoritative.  For  the  private  com- 
parison of  various  batches  of  one  variety  or  make  of  plates,  the  Warnerke,  or  any  one  of 
the  various  forms  of  sensitometer  that  have  been  suggested,  may  do  well  enough,  but  as 
means  of  conveying  information  as  to  the  sensitiveness  of  plates  in  general,  it  is  utterly 
useless :  a  pretty  toy,  and  nothing  more.  The  alkaline  sulphide  from  which  the  so- 
called  standard  light  is  obtained  varies  in  its  power  of  absorption  and  of  evolution  almost 
as  much  as  did  collodion  in  sensitiveness,  and  the  screens  sent  out  with  the  instruments 
seem  to  vary  as  much  as  the  luminous  tablets. 


EXPOSURE,    OR    THE    QUESTION    OF    TIME. 


237 


With  what  has  already  been  hinted  at  in  the  notes  and  in  the  text,  it  hardly 
seems  necessary  to  say  more.  There  is  no  real  rule  for  exposure.  There  are 
thousands  of  chances  to  do  right. 

The  conditions  essential  to  a  really  useful  sensitometer  are  that  the  light  employed 
shall  be  uniform  in  quality  and  quantity,  from  whatever  source  it  is  obtained,  and  that 
the  graduated  screen  shall  be  a  mathematically  correct  mechanical  production  that  can 
be  made  by  anyone  trained  to  exact  work.  The  light  should  also  approach  as  near  as 
possible  to  that  of  pure  diifused  sunlight.  It  is  well  known  that  the  light  produced  by 
the  oxidation  of  magnesium  approaches  more  nearly  to  ordinary  sunlight  than  any  other 
form  of  artificial  light,  and  that  the  quantity  emitted  from  the  rapid  combustion  of  any 
given  weight  is  a  constant  quantity.  I  believe,  then,  that  a  convenient  and  thoroughly 
practical  standard  light  for  sensitometer  purposes  will  be  found  in  the  flash  produced  by 
the  ignition  of  an  accurately  weighed  quantity  of  a  uniform  mixture  of  magnesium  in 
powder  of  a  certain  degree  of  fineness,  and  chlorate  or  nitrate  of  potash  in  fine  powder. 
The  degree  of  fineness,  and  the  proportions  in  which  the  nitrogen  should  be  mixed, 
should  be  matter  of  careful  experiment.  It  should  be  undertaken  by  one  of  our  photo- 
'  graphic  societies. 

The  kind  of  screen  that  recommends  itself  to  me,  as  likely  to  answer  most  perfectly,  is 
a  mechanical  arrangement  that  appeared  in  the  British  Journal  of  Photography  some 
years  ago  ( Fig.  238).  Practically 
it  consists  of  a  square  box  so 
divided  as  to  represent  any  de- 
sired number  of  square  tubes — 
nine,  of  two  inches  square  and 
three  inches  deep,  should  an- 
swer admirably,  and  would  as- 
sume the  form  of  a  box  6x6x3 
inches. 

One  side  of  the  box,  or  one 
«nd  of  the  tubes,  is  fitted  so  as 
to  receive  a  plate  holder  or  dark 
slide,  in  which  the  plate  is 
placed,  and  the  other  side,  or 
end  of  the  tubes,  is  covered  by 
a  metallic  plate  in  which  are 
drilled  nine  holes,  each  in  the 
centre  of  one  of  the  square  tubes, 
and  each  exactly  twice  the  value 
in  light-admitting  area  of  its 

predecessor.  The  size  of  the  openings,  distance  of  the  flash  from  the  plate,  and  quantity 
of  magnesium  flashed,  could  easily  be  arranged,  so  that  the  nine  numbers  would  include 
plates  from  the  slowest  to  the  most  rapid  in  use  at  present;  and  while  a  sensitometer  thus 
arranged  might  not  be  altogether  perfect,  it  certainly  would  approximate  more  nearly  to 


FIG.  238. 


238 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


Keep  on  the  alert  for  these  chances — draw  on  your  fund  of  knowledge  to 
help  you  when  they  are  presented,  then  your  results  will  surely  do  you  credit. 

perfection,  and  convey  a  more  correct  knowledge  of  the  true  sensitiveness  of  a  plate  than 
any  form  of  instrument  that  has  as  yet  been  proposed. — DR.  JOHN  NICOL. 

My  photometer  is  a  simple  prism  made  of  yellow  glass  (Fig.  239,  side  view),  framed  in 
such  a  manner  as  to  become  an  ornament  for  a  watch  chain.  Upon  the  inner  surface  of 
this  yellow  glass  prism  lines  are  drawn  beginning  from  1  to  10;  No.  1  represents  the 
finest  part  of  the  prism,  and  No.  10  the  thickest.  A  piece  of  sensitized  paper  is  intro- 


FIG.  239. 


Fro.  2-10. 


duced  under  the  prism  and  allowed  to  remain  one  minute  (in  the  shade  it  is  then 
examined),  and  according  to  the  number  that  the  impression  has  reached,  it  is  very  easy 
to  calculate  the  photogenic  power  of  the  light. 

In  order  to  give  my  readers  a  correct  idea  of  this  photometer,  I  inclose  two  sketches  of 
the  exact  size  of  the  instrument.  Fig.  239  is  a  side  view  of  the  glass  prism  before  being 
mounted ;  Fig.  240,  the  front  view  of  same  when  framed. — J.  FLEURY  HERMAGIS. 


CHAPTER    XII. 

CONCERNING   CHEMICALS. 

109.  The  next  halt  in  our  picture  making  pilgrimage  must  be  made  at  the 
chemical  hostelry. 

Rough  treatment  is  sometimes  visited  upon  both  novice  and  veteran  in  this 
quarter. 

The  glacier  of  the  Rhone  does  not  twist  and  turn,  and  break  up  and  change 
with  more  eccentric  independence  than  does  the  vast  out-pour  and  down-pour 
of  chemical  elements,  equivalents,  and  combinations. 

And  yet,  where  is  there  anything  more  grandly  beautiful  than  the  Rhone 
glacier — where  anything  so  superb  as  the  actions  and  reactions  which  occur  in 
the  chemistry  of  photography  ? 

It  would  be  advantageous  if  all  brave  enough  to  enter  our  art's  discipleship, 
were  well  versed  in  the  outlines  at  least,  of  chemistry,  but  it  is  not  within  the 
province  of  this  work  to  supply  such  information.  It  can  be  had  readily  in 
the  books  if  it  is  desired.1 

110.  The  number  of  substances  which  are  chemically  decomposed  by  light 
is  great ;  when  the  product  of  decomposition,  as  ordinarily,  has  another  color 
than  the  original  substance,  a  picture  by  effect  of  light,  so  to  say  a  photographic 
picture,  can  be  produced  with  any  of  these  substances,  by  exposing  a  surface 
covered  with  it  under  a  pattern,  or  photographic  negative,  or  in  the  camera. 
The  juices  of  many  plants  and  flowers  may  be  used  in  this  way.     In  fact, 
nature  herself  is  one  of  the  most  agile  photographers.     Like  much  of  her 
work,  however,  her  pictures  are  fugitive — or  her  latent  likenesses  go  unde- 
veloped.    The  pictures  on  silvered  paper,  the  common  photographs,  are  suffi- 
ciently colored,  but  pictures  produced  in  this  way  on  paper  impregnated  with 
the  salts  of  oxide  of  iron,  uranium,  chromic  acid,  etc.,  are  very  weakly  colored. 
However,  the  products  of  decomposition,  the  suboxides  of  iron,  uranium,  etc., 
may,  by  simple  chemical  reactions,  be  transformed  into  other  compounds  of 
intense  color.     In  that  manner  pictures  in  Berlin  blue,  in  aniline  colors,  and 

1  See  "Outlines  of  Chemistry,"  by  Henry  M.  Mclntire,  M.E.,  in  Philadelphia  Photographer,  1878,  vol.  xv. 

(239) 


240        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

others  are  produced.     In  all  these  processes  a  long  time  and  intense  light  are 
necessary  to  obtain  a  sufficiently  colored  picture. 

It  is  Daguerre's  and  Fox  Talbot's  great  discovery,  that  iodide,  bromide,  and 
chloride  of  silver  have  the  faculty  of  photographic  development;  this  enables  us 
to  take  a  picture  by  a  short  exposure,  and  has  engendered  the  art  of  photog- 
raphy. The  sensitive  Daguerrian,  collodion,  or  emulsion-plate  gets,  by  ex- 
posure, the  so-called  invisible  picture — that  is,  a  very  weak  picture  of  slightly 
decomposed  iodide  or  bromide  of  silver.  By  development,  the  invisible  picture 
is  coated  with  a  proportionate  deposit  of  silver ;  the  silver  deposit  which  con- 
stitutes the  developed  picture  is  not  the  product  of  a  chemical  reaction  with 
the  invisible  picture,  but  originates  by  a  peculiar  physical  property  of  the  latter ; 
namely,  photographic  attraction. 

111.  The  photographic  development  is  only  rarely  known  with  any  other 
substance  than  the  iodide,  bromide,  and  chloride  of  silver.     The  development 
of  the  picture  in  Poitevin's  process  with  tartrate  of  iron,  which  consists  in 
sticking  any  powdery  substance  to  the  exposed  parts,  cannot  be  paralleled  with 
it,  neither  can  the  bichromate  solutions  used  in  carbon  and  kindred  processes  be 
considered  in  the  same  category. 

Dr.  Shultz  Sellack  found  that  the  haloid-salts  of  copper,  iodide  and  bromide  of 
copper,  have  the  faculty  of  photographic  development  like  the  salts  of  silver.  A 
plate  of  pure  copper,  iodized  or  bromized  as  in  Daguerre's  process  and  exposed 
in  the  camera,  develops  a  picture  in  mercurial  vapors.  Also,  when  the  brom- 
ized or  iodized  copper-plate  is  sufficiently  exposed  under  a  photographic  nega- 
tive, a  picture  is  produced  which  can  be  fixed  by  hyposulphite.  The  sensitive 
copper-plate,  therefore,  acts  exactly  like  the  Daguerrian  plate.  A  process 
similar  to  the  wet  collodion  or  emulsion  process  is  impracticable  with  the  salts 
of  copper  on  account  of  their  solubility  in  water. 

112.  A  good  deal  of  discussion  has  taken  place  among  photographic  ex- 

112.  A  month  ago  I  took  a  view  upon  a  7x9  plate.  After  development,  I  heated  it 
with  a  weak  solution  of  acid  pernitrate  of  mercury;  with  a  clean  wooden  spatula,  I 
scraped  the  film  off  the  glass  into  a  clean  porcelain  crucible,  and  placed  it  over  a  Bunsen 
burner.  After  slowly  drying  the  film,  I  raised  the  heat  gradually  to  redness-;  portions 
of  the  film,  as  the  heat  increased,  flashed  slowly  off  like  wet  gunpowder,  and  at  last  it 
was  completely  consumed,  -leaving  no  ash  whatever  behind:  a  slight  yellowish  stain  about 
a  quarter  inch  long,  and  a  sixteenth  wide  alone  remained.  This  stain  I  treated  with 
chlorine  water,  without  producing  any  change  in  its  color,  and  next  with  ammonia  and 
various  acids  successively,  but  without  any  visible  effect  whatsoever. 

Thinking  that  this  experiment  indicated  very  strongly  that  no  salt  of  silver  remained 


CONCERNING    CHEMICALS.  241 

perimentalists  as  to  the  nature  of  the  latent  image,  whether  it  be  chemical  or 
physical.  Much  industrious  experiment  was  followed  by  the  advocates  on 
both  sides,  with  interesting  and  curious  results  but  ending  with  diverse  conclu- 
sions. Those  who  enter  only  into  the  practical,  share  whatever  advantages 

behind,  after  subjecting  the  film  as  described  to  the  solvent  action  of  the  acid  pernitrate 
of  mercury,  I  coated,  exposed,  and  developed  successively  seven  7x9  plates,  with  the 
same  bromo-iodized  collodion,  and,  avoiding  purposely  the  collo-developer,  used  a  plain 
iron  developer,  the  same  for  each. 

The  remaining  six  films  I  scraped  off  with  care  into  a  beaker,  and  added  about  an 
ounce  and  a  half  of  distilled  water  and  a  small  bit  of  pure  zinc.  I  then  added  pure 
dilute  sulphuric  acid,  and  kept  up  the  action  for  a  week,  by  adding  a  few  drops  addi- 
tional, from  time  to  time,  until  the  zinc  was  wholly  dissolved. 

At  the  end  of  this  time  I  added  twenty  drops  of  pure  nitric  acid,  and  gradually  raised 
the  heat  to  boiling.  No  change  in  the  appearance  of  the  liquid  or  films  took  place  under 
the  above  treatment. 

I  now  filtered  off  about  four  drachms  of  the  liquid,  diluted  slightly,  and  added  to  this 
two  drops  of  dilute  hydrochloric  acid ;  not  the  slightest  cloud  or  opalescence  was  formed, 
or  any  change  whatsoever.  I  then  repeated  this  experiment,  after  slowly  evaporating 
the  liquid  to  about  a  quarter  of  its  original  bulk,  but  without  any  effect  of  any  sort.  The 
transparency  of  the  liquid  continued  perfect. 

So  far  as  this  mode  of  investigation  will  indicate,  it  is  therefore  evident  that  no  silver 
salt  was  present  in  a  half  dozen  7x9  films,  on  each  of  which  an  image  could  be  redevel- 
oped after  its  treatment  to  perfect  transparency  by  the  acid  pernitrate  of  mercury  and 
this  experiment  also  confirms  the  first. 

Now,  here  is  the  film,  apparently  reduced  to  pure  pyroxyHn,  and  apparently  deprived 
of  all  substances  capable  of  exercising  any  chemical  action  on  the  silver  and  iron  devel- 
oper whatever,  and  yet,  to  it  has  been  conveyed  a  power  to  cause  the  particles  of  silver 
as  they  fall  from  the  developer  to  assume  the  form  of  the  picture  to  which  it  has  been 
exposed  in  the  camera.  What  is  this  power?  It  is  a  persistent  power,  for  the  trans- 
parent film  on  which  it  is  impressed  may  be  dried,  and  the  image  be  redeveloped  the 
next  day  by  the  usual  mode  of  developing  tannin  plates. — THOS.  P.  SHEPARD,  M.D. 

Simple  pressure,  I  find,  modifies  iodide  of  silver  in  such  a  way  as  to  make  it  capable  of 
receiving  a  development. 

An  orange-wood  ruler  was  selected,  in  which  the  letters  composing  the  word  "Sor- 
rento" had  been  carved  in  open  work,  cut  entirely  through.  A  plate  was  sensitized  in 
the-  usual  manner,  and  then,  without  removing  it  from  the  dark-room,  the  ruler  was  laid 
upon  the  sensitive  film,  and  whilst  the  glass  rested  on  a  firm  support,  the  ruler  was 
powerfully  pressed  down  upon  it  by  the  full  strength  of  the  two  hands,  and  kept  so  for 
twenty  or  thirty  seconds. 

The  ruler  was  then  carefully  lifted  off,  and  the  plate  developed  with  an  iron  developer. 
The  word  immediately  became  visible. 

Precisely  as  I  expected,  it  was  the  parts  which  had  been  pressed  that  received  the 
silver  deposit.  Had  the  reverse  taken  place,  it  might  have  been  said  that  the  ruler  car- 

16 


242        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

come  from  such  discussion  while  they  move  on,  giving  their  best  attention  to 
what  really  concerns  their  actual  work. 

113.  It  should  be  the  care  of  every  ambitious  photographer  to  secure  chemi- 
cals which  are  pure  and  of  proper  strength.     There  should  never  be  any 
variation  in  the  first  quality.     "  The  best "  is  never  more  emphatically  "  the 
cheapest "  than  in  the  line  of  chemicals,  for,  I  might  say,  a  single  molecule  of 
badness  may  upset  a  whole  dark-room. 

114.  Chemicals  are  very  sensitive  to  atmospheric  influences,  and  must  be 
carefully  humored  to  adapt  them  to  changes  in  temperature. 

ried  away  a  portion  of  the  silver  solution,  so  that  the  letters  were  left  with  more  nitrate 
on  them ;  or  that  the  faint  light  of  the  dark-room  had  acted  on  the  open  part  under  the 
letters,  whilst  pressure  was  applied. 

I  cannot  but  think  that  these  experiments  will  afford  a  most  telling  argument  in  favor 
of  the  physical  theory,  and  one  which  its  opponents  will  find  it  difficult  to  explain  away. 
Here  is  no  possibility  of  reduction,  no  possible  production  of  metallic  silver,  or  of  sub- 
iodide,  no  possible  elimination  of  iodine,  and  yet  a  developable  impression  is  produced, 
which  comes  out  plain  and  strong  under  the  action  of  a  developer. 

It  is  almost  superfluous  to  remark  that  the  foregoing  experiment  may  be  almost  in- 
definitely modified,  the  one  essential  thing  only,  seeming  to  be  pressure.  Marks  made, 
probably,  by  any  hard  body,  may  be  brought  out  by  the  development,  always  the  part 
receiving  the  pressure  becoming  darkened  in  the  development. — M.  CAREY  LEA,  M.D. 

113.  As  another  month  is  close  at  hand,  we  are  verging  into  summer's  longest  days, 
and  the  penetrating  rays  of  the  great  demon  of  light  shine  straight  down  upon  us.    This, 
no  doubt,  is  the  most  perplexing  season  during  the  whole  year  to  the  photographic 
manipulators.     This  is  due  to  intense  heat  and  strength  of  chemicals.     How  many  of 
the  readers  of  the  Philadelphia  Photographer  can  call  back  to  memory  the  perplexity  of 
working  chemicals  on  a  hot  sultry  day  in  midsummer?     When  it  was  cooler,  a  day  or 
two  before,  all  worked  in  harmony,  and  they  rejoiced  over  their  success  and  flattering 
results. 

I  can  remember  well  when  the  foggy  mists  first  visited  me.  No  richness ;  no  round- 
ness; no  beauty.  No!  Nothing  but  dead,  flat,  inexpressive  results.  Sitters  out  of 
patience,  and  chemicals  out  of  order,  and  I  at  my  wit's  end,  almost  suffocating,  locked 
up  my  room,  and  commenced  to  make  up  new  chemicals.  With  care  and  cleanliness,  I 
obtained  results  foe  simile  to  the  day  before.  I  wished  I  had  never  seen  a  gallery  or  a 
picture,  and  my  money  invested  in  something  else  more  profitable.  But  there  is  "a  calm 
after  a  storm."  My  chemicals  work  smooth  and  uniformly ;  the  hot  weather  does  not 
seem  to  affect  them.  Why?  Simply  because  I  reduced  their  strength.  Since  that  time 
I  have  used  my  chemicals  thirty  per  cent,  weaker  in  summer  than  in  winter. 

Therefore,  I  say  to  beginners,  as  soon  as  the  foggy  days  come  weaken  your  chemicals, 
and  be  careful  in  preparing  them,  and  you  will  be  rewarded  with  astonishing  results. — 
W.  W.  BALDWIN. 

114.  Too  much  importance  cannot  be  attached  to  watching  the  temperature.     Those 


CONCERNING    CHEMICALS.  243 

The  solutions  should  be  used  weaker  in  summer  than  in  winter,  and  at  all 
seasons  their  temperature  is  better  uniform.  You  are  riding  a  bicycle  while 
you  are  handling  them.  The  road  is  never  twice  alike — rarely  smooth  and 

who  have  always  had  the  good  fortune  to  work  in  first-class  rooms,  always  kept  at  a 
warm  temperature  int  winter  (for  it  is  at  this  season  that  troubles  from  this  cause  mostly 
arise),  with  every  facility,  can  scarcely  appreciate  the  difficulties  that  sometimes  occur, 
from  variations  of  temperature,  to  their  less  favored  brethren ;  and  even  those  who  have 
first-class  facilities  often  fail  to  provide  for  this  most  important  contingency. 

It  was  forcibly  brought  to  my  mind  this  winter  by  the  change  caused  on  account  of 
working  in  a  new  dark-room,  not  provided  with  the  means  of  warming  and  keeping 
warm  the  silver  solution,  especially  as  the  temperature  fell  greatly  at  night,  on  account 
of  the  fires  not  being  fully  kept  up  then.  It  was  a  subject  of  remark  in  our  establish- 
ment— the  difference  in  chemical  effects  produced  in  the  dark-room  attached  to  the  old 
light,  and  that  of  the  new. 

Every  morning,  until  the  temperature  of  the  room  had  been  up  to  seventy  degrees, 
and  for  over  three  or  four  hours,  the  plates  would  coat  slow,  with  liability  to  streak,  work 
slow,  and  develop  slow ;  while  heating  the  developer  made  the  liability  to  streak  only 
more  manifest,  as,  in  order  to  produce  good  effects,  the  bath  and  developer  should  be  of 
nearly  equal  temperature. 

Nothing  has  greater  influence  on  sensitiveness  than  the  temperature  before  or  after  develop- 
ment. Of  course,  the  developer  must  be  warmed  also ;  but  the  full  benefit  is  to  be  de- 
rived by  having  this  a  few  degrees  warmer  than  the  bath,  but  very  little.  When  a  cold 
bath  is  used,  and  a  warm  developer,  the  image  will  develop  more  rapidly  than  with  a 
cold  solution ;  but  no  more  detail  will  appear  than  with  the  latter.  It  must  be  borne  in 
mind  that  when  the  chemicals  are  kept  up  to  the  temperature  mentioned,  the  bath  must 
be  weaker  than  when  used  cold. 

I  find,  in  examining  our  negatives,  that  the  best  results  are  obtained  in  the  spring 
and  fall  months,  and  in  summer,  when  the  temperature  is  not  over  80°.  Extremely  hot 
weather  has  its  drawbacks,  and  causes  too  rapid  drying  of  the  plates ;  but  if  the  dark- 
room be  not  excessively  hot,  very  little  trouble  is  experienced,  in  comparison  to  that 
caused  by  a  cold  room  in  winter. 

One  point  must  not  be  lost  sight  of,  viz.,  that  the  temperature  of  the  plate,  at  the  time 
of  exposure,  exerts  a  greater  influence  than  any  one  thing,  so  far  as  temperature  is  con- 
cerned. Using  a  warm  developer  on  a  cold  plate  helps  but  little,  and  often  causes  greater 
inequalities  in  the  result. 

The  greatest  amount  of  sensitiveness  is  obtained  when  there  is  the  least  difference  in 
strength  between  the  bath  and  the  salts  in  the  collodion  consistent  with  rapid  coating; 
which  result  is  to  be  obtained  only  by  keeping  the  bath  solution  at  a  good  average  tem- 
perature.— D.  BACHRACH,  JR. 

Attention  has  often  been  called  to  the  fact  that  chloride  of  silver  is  far  less  soluble  in 
cold  than  in  warm  solution  of  hyposulphite  of  soda ;  and,  though  no  evil  may  be  antici- 
pated from  using  the  solution  of  the  usual  strength  in  accustomed  operations,  the  fact 
remains  that  more  time  is  required,  for  instance,  to  fix  a  print  when  the  temperature  of 


244        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

never  the  same  for  a  whole  day  at  a  time.  You  are,  therefore,  required  to  be 
on  the  alert  continually. 

115.  I  have  spoken  of  atmospheric  changes.  The  air  is  one  of  the  worst 
disturbers  of  the  peace  there  is,  so  that  protection  against  its  influences  is  quite 
an  essential  thing  to  look  after.  It  not  only  deteriorates  the  solutions,  decom- 
poses and  discolors  them,  but  in  the  most  wily  way  sometimes  saps  their 
strength. 

the  solution  is  low  than  would  be  needed  under  ordinary  circumstances.  And  it  is  under 
such  contingencies — cold  solutions,  cold  atmosphere,  and  general  cheeriness  of  working 
— that  assistants,  unless  with  a  fine  moral  sense,  are  apt  to  hurry  rather  than  linger  over 
their  work,  as  chemical  requirements  really  would  indicate.  Hence,  during  all  cold 
weather  it  may  be  taken  as  a  standard  rule  that  the  fixing  solution  should  be  of  a  slightly 
increased  strength. 

Naturally,  it  will  not  be  necessary,  where  perfect  arrangements  exist  for  keeping  the 
dark-room  at  a  uniform  heat,  to  make  so  material  an  alteration  in  the  proportions,  but 
it  must  ever  be  borne  in  mind  that  a  temperature  which,  on  a  winter's  day,  would  be 
considered  warm  and  comfortable,  would  in  summer-time  produce  a  feeling  of  chill. 
Thus  no  operator  would  complain  of  a  dark-room  at  forty-eight  or  fifty  degrees  in  winter, 
though  in  summer  he  would  consider  it  actually  cold.  Again,  there  are  very  few  rooms 
where,  night  and  day,  the  heating  is  kept  up. — BE,.  JOURNAL. 

115.  When  it  is  desired  to  protect  oxidizable  aqueous  solutions  from  the  action  of  air, 
the  best  plan  is  to  take  advantage  of  the  properties  of  the  paraffines,  for  paraffine, 
whether  solid  or  liquid,  will  effectually  exclude  the  air  on  the  one  hand,  and  prevent 
evaporation  of  the  water  on  the  other.  Few  chemical  substances  will  attack  it,  and 
among  those  which  do  so  are  none  likely  to  be  used  in  photography.  Some  photogra- 
phers already  use  common  liquid  paraffine  upon  the  top  of  their  stock  developer,  to 
protect  it  from  the  air,  for  then  it  is  safe  even  from  the  attacks  of  the  air  inside  the  top 
of  the  bottle.  A  device  has,  however,  to  be  called  into  play  to  draw  off  some  of  the 
developer  when  wanted ;  as  simple  a  plan  as  any  would  be  to  use  a  little  glass  barrel  with 
a  glass  tap,  and  cover  the  developer  with  half  an  inch  in  depth  of  liquid  paraffine.  The 
tap  should  be  lubricated  with  another  paraffine,  namely,  vaseline. 

The  imperfections  of  common  ground-glass  stoppers  as  a  means  of  excluding  air  from 
the  interior  of  bottles,  is  scarcely  sufficiently  recognized.  Ground-glass  consists  of  an 
infinite  multitude  of  small  hills  and  valleys ;  consequently,  when  two  such  rough  surfaces 
are  laid  one  against  the  other,  plenty  of  small  irregular  channels  exist,  through  which 
air  can  pass  between  the  pieces  of  glass.  Alterations  in  temperature  exercise  a  pumping 
action  inside  common-stoppered  bottles;  the  interior  air  or  vapor  expands  by^heat,  and 
contracts  by  cold,  thus  causing  currents  backward  and  forward  along  the  space  between 
the  stopper  and  the  neck  of  the  bottle,  but  the  little  channels  being  so  very  small, 
the  pumping  action  is  much  retarded.  For  many  purposes  a  good  cork  is  in  several 
respects  more  convenient  than  a  stopper  of  the  common  type. 

Coming  now  to  the  question  of  the  best  lubricants  for  stoppers,  the  paraffines  stand  at 


CONCERNING    CHEMICALS.  245 

Again,  air  becomes  a  pest  when  it  finds  its  way  into  the  solutions  in  too 
great  quantities,  so  that  its  expulsion  becomes  sometimes  quite  a  matter  of  labor 
and  anxious  care. 

116.  Pure  water  is  one  of  the  absolute  requirements  of  success  in  photo- 
graphic chemistry.  It  need  not  always  be  distilled,  but  it  should  be  chemically 
pure. 

the  head  of  the  list  for  the  protection  of  all  but  the  few  chemicals  which  attack  or  dis- 
solve them,  their  affinities  being  of  the  most  limited.  The  hardest  of  the  series,  and  the 
one  which  has  the  highest  melting  point,  is  the  mineral  paraffine,  ozokerit ;  next  come 
the  softer  paraffines,  produced  in  the  destructive  distillation  of  vegetable  matter,  and 
which  can  be  obtained  with  varying  degrees  of  hardness ;  next  come  vaseline  and  ozo- 
kerine,  which  are  of  the  consistency  of  soft  grease,  and,  last  of  all,  the  liquid  paraffines 
are  available.  Vaseline  and  ozokerine  are  the  best  substances  for  lubricating  the  stoppers 
of  bottles;  should  the  two  substances  for  some  purposes  not  be  deemed  hard  enough,  by 
mixing  with  them  one  of  the  softer  solid  paraffines,  a  hydro-carbon  paste  of  any  desired 
consistency  can  be  obtained. — W.  H.  HARRISON. 

116.  Pure  water  is  something  in  which  everybody  should  be  interested,  but  to  the  pho- 
tographer it  is  a  necessity,  if  he  would  avoid  numerous  vexations  and  trouble.  There 
are  many  methods  employed  by  the  disciples  of  the  art  for  obtaining  the  necessary 
article,  but  most  of  them  are  open  to  more  or  less  objection. 

During  my  recent  experiments  with  bromized  gelatine  emulsion,  knowing  the  very 
sensitive  nature  of  gelatine  to  evil  influences,  and  its  proneness  to  act  just  as  badly  as  it 
can  under  all  circumstances,  sometimes  taking  advantage  of  the  slightest  departure  from 
the  proper  course  and  procedure  on  the  part  of  the  operator  to  spoil  the  whole  batch,  I 
found  myself  at  a  loss  to  know  how  to  obtain  pure  water. 

I  had  a  tin  can  made  three  inches  greater  in  diameter  than  the  bottle  I  used,  and  three 
inches  deeper.  One  end  of  the  can  was  left  open,  and  a  tin  bottom  placed  in  the  other 
end,  with  a  neck  in  its  centre  a  half  inch  larger  in  diameter  than  the  neck  of  the  bottle, 
and  a  little  shorter. 

The  bottle  was  then  placed  in  the  can  bottom  up,  the  neck  of  the  bottle  inside  of  the 
neck  of  the  can.  Four  tin  braces  were  then  soldered  to  the  sides  of  the  can  inside, 
around  the  bottom,  their  object  being  to  hold  the  bottle  in  place  in  the  centre  of  the  can. 

A  strip  of  tin  two  inches  wide,  with  turned  edges  to  render  it  stiff,  was  then  placed 
across  the  centre  of  the  inside  of  the  can,  one  edge  resting  firmly  against  the  bottom  of 
the  bottle,  and  its  ends  firmly  soldered  to  the  sides  of  the  can. 

The  object  of  this  strip  is  to  hold  the  bottle  down  securely  when  the  can  is  full  of 
water.  The  space  between  the  tin  neck  of  the  can  and  the  neck  of  the  bottle  was  then 
filled  with  plaster-of-Paris  cement,  rendering  it  water-tight. 

I  then  took  a  piece  of  glass  tube  about  eighteen  inches  long,  and  six  inches  from  one 
end  I  made  a  right-angled  bend,  by  holding  the  tube  in  the  flame  of  a  spirit-lamp  until 
heated  sufficiently  to  bend.  The  can  was  then  set  upright  on  a  suitable  support,  which, 
of  course,  placed  the  bottle  inside  of  it  inverted,  with  its  neck  protruding  downwards 
through  the  bottom  of  the  can.  The  can  was  then  filled  with  cold  water. 


246 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  241. 


There  are  many  methods  in  use  for  obtaining  pure  water.  For  some  pur- 
poses it  may  be  rendered  so  by  easy  chemical  means,  while  for  others  it  must  be 
distilled  or  boiled.  The  means  will  be  explained  as  we  proceed. 

•i 

The  short  arm  of  the  glass  tube  was  then  placed  upward  through  the  neck  of  the 
bottle,  fitting  loosely,  and  the  other  end  of  the  tube  was  placed  in  the  spout  of  a  boiling 

tea-kettle,  the  joint  between  the  spout  and  tube 
being  wound  with  a  strip  of  muslin,  to  render 
it  nearly  steam-tight.  The  steam  from  the  tea- 
kettle now  passed  through  the  glass  tube  up 
into  the  bottle,  and  coming  against  the  cold 
sides  of  the  bottle  was  condensed,  and  ran 
down  out  of  the  neck  of  the  bottle  into  a  glass 
,  dish  placed  below  to  receive  it. 

h]  fj^- — I  The  condensed  steam  coming  only  in  contact 

][_  jj,  with  glass  surfaces  produces  water  absolutely 

pure,  provided  the  manipulation  is  intelligently 
and  carefully  conducted. 

The  accompanying*  rough  diagram  will  give 
a  general  idea  of  the  construction  of  the  appa- 
ratus. A  is  the  bottle,  B  the  t'.n  can,  (7 the  bent  glass  tube,  and  D  the  spout  of  the  tea- 
kettle.— JAY  DENSMORE. 

The  published  instructions  issued  by  the  Eastman  Company  for  the  preparation  of  the 
developer  for  use  with  their  negative  paper,  raise  the  question  in  the  mind  of  the  reader 
why  the  solution  does  not  deteriorate  in  a  very  short  time ;  yet  I  was  told  that  some  of 
it,  of  light  color,  which  I  saw  in  use  on  their  premises,  had  been  prepared  a  fortnight 
before.  The  official  formula  is :  Warm  water,  sixteen  ounces ;  sulphite  sodium  crystals, 
pure,  half  a  pound ;  allow  to  cool,  and  add  one  ounce  of  pyrogallic  acid,  and  then  a 
quarter  of  a  pound  of  carbonate  of  soda  (not  bicarbonate  of  soda).  For  use,  dilute  one 
part  of  stock  solution  with  four  of  water.  Thus  but  one  solution  is  used  for  developing 
purposes,  except  in  cases  of  over-exposure,  when  a  little  bromide  of  potassium  is  added. 
Here,  then,  is  a  highly  alkaline  developer  which  keeps,  so  I  asked  the  operator  why  it 
did  not  blacken  and  decompose  rapidly.  He  replied  that  it  depended  upon  using  water 
which  had  been  boiled ;  if  unboiled  water  with  the  normal  proportion  of  air  in  it  were 
substituted,  the  developer  would  blacken  rapidly,  and  go  on  blackening,  he  said,  after  it 
had  absorbed  all  the  oxygen  of  the  air  held  in  solution  in  the  first  instance,  by  the  water. 
The  sulphite  of  soda  must  also  be  very  pure;  indeed,  the  photographic  merits  of  this 
salt  never  come  out  unless  it  is  pure. 

The  foregoing  facts  seem  to  show  that  there  are  great  advantages  is  using  boiled  water 
for  pyrogallol  stock  solutions,  and  this,  combined  with  M.  Audra's  system  of  develop- 
ment, will  conduce  to  comfort  and  efficiency  in  the  future  use  of  this  unstable  organic 
absorbent  of  oxygen.  Boiling  for  a  few  minutes  does  not  get  rid  of  the  whole  of  the  air 
and  traces  of  other  gases  dissolved  in  water,  and  perhaps  the  properties  of  water  properly 
freed  from  dissolving  gases  might  be  worth  trying  in  photography. 


CONCERNING    CHEMICALS.  247 

Tests  for  the  purity  of  photographic  chemicals  are  not  often  rendered  neces- 
sary in  these  enlightened  days  of  photography,  for  the  reason  that  no  reputable 
dealer  will  dispense  a  bad  quality  willingly. 

If  the  photographer  is  in  doubt,  however,  he  is  unwise  to  continue  using 

Rain  water,  after  a  prolonged  downpour  to  clear  away  the  floating  dirt  in  the  atmos- 
phere, is  the  purest  water  naturally  available,  it  having  been  distilled  by  the  heat  of  the 
sun ;  but  every  hundred  cubic  inches  of  such  water  contain  about  two  and  a  half  cubic 
inches  of  air  and  of  gases  mixed  in  small  proportion  with  the  said  air.  Water  freshly 
distilled  is  not  free  from  air.  To  get  rid  of  this  air,  it  is  necessary  to  boil  the  water 
steadily  for  not  less  than  one  hour,  with  brisk  boiling  for  a  few  minutes  at  the  close, 
to  drive  all  the  air  out  of  the  neck  of  the  flask,  when  it  is  intended  to  close  the  latter, 
which  should  be  strong  enough  to  bear  the  pressure  of  the  external  atmosphere,  when, 
by  cooling,  a  comparative  vacuum  is  produced  in  the  upper  part  of  the  vessel. 

The  remarkable  instrument,  the  water-hammer,  is  made  by  taking  a  V-shaped  glass 
tube,  say,  with  each  of  its  legs  eighteen  inches  long,  and  an  inch  in  diameter ;  this  tube 
is  closed  at  one  end.  Thoroughly  boiled  water  is  made  to  fill  the  tube,  and  is  then  boiled 
nearly  half  away  in  the  tube  itself;  when  the  ebullition  is  at  its  briskest  the  open  end  of 
the  tube  is  softened  by  heat,  the  tube  is  then  withdrawn  from  the  flame  which  produces 
the  ebullition,  and  the  moment  that  ebullition  ceases  the  softened  opening  of  the  tube  is 
closed.  Thus  enough  well-boiled  water  is  left  in  the  tube  to  fill  one  of  its  legs  com- 
pletely, and  about  one-fourth  of  the  other  leg.  If  the  water-hammer  be  turned  bottom 
upwards,  thus  A.  when  one  of  its  legs  is  quite  full,  the  water  in  the  other  leg  will  not 
fall ;  it  refuses  to  obey  the  law  of  gravity  unless  the  tube  be  tapped,  and  when  the  water 
is  made  to  fall  it  produces  a  somewhat  metallic  sound,  like  one  hard  solid  body  striking 
another.  In  fact,  air  in  water  acts  as  a  kind  of  elastic  spring,  and  when  that  air  is 
removed  the  particles  of  the  water  lock  themselves  more  firmly  together.  Thus  water, 
scientifically  boiled  until  it  is  free  from  air,  has  curious  properties,  and  whether  it  will 
by  absorption  permeate  an  air-charged  gelatine  film  more  rapidly  than  other  water,  or 
whether  it  will  exercise  any  influence  upon  the  delicately  balanced  phenomena  of  pho- 
tographic development,  is  worth  trying. — W.  H.  HARRISON. 

The  carbonic  acid  contained  in  ordinary  water  tends  to  the  injury  of  photographic 
prints  in  the  washing  stages.  Mr.  W.  M.  Ashman  pointed  out  the  injury  done  to  prints 
by  washing  water  containing  carbonate  of  lime,  especially  when  particular  samples  of 
paper  were  used. 

Pure  carbonate  of  lime,  and  carbonate  of  magnesia,  are  both  insoluble  in  pure  water, 
but  are  soluble  in  water  containing  carbonic  acid  gas.  A  gallon  of  rain-water  usually 
contains  four  cubic  inches  of  nitrogen,  two  cubic  inches  of  oxygen,  and  one  cubic  inch 
of  carbonic  acid.  The  latter  is  the  solvent  of  the  chalk  and  limestone  rocks ;  the  minute 
traces  of  carbonic  acid  in  water  carved  most  of  the  beautiful  scenery  of  Derbyshire,  cut 
its  river  beds  deep  in  rocks  and  dissolved  out  its  caverns,  carrying  off  in  weak  solution 
its  limestone  and  its  chalk,  to  injure  the  prints  of  inoffensive  and  unsuspecting  photog- 
raphers living  lower  down  on  the  banks  of  the  rivers.  Because  of  the  solvent  action  of 
carbonic  acid  in  water,  the  scenery  of  extensive  limestone  regions  is  always  beautiful ; 


248          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

what  does  not  seem  to  give  him  the  very  best  results.  There  is  no  excuse 
whatever  for  the  production  of  bad  photographs  when  such  perfect  appliances 
and  such  excellent  materials  are  to  be  had  readily  in  the  best  market  in  the 
world. 

117.  In  all  things  be  exact — even  "old  maidish."  It  is  just  as  easy  once 
the  bad  habits  are  broken  and  careful  ones  acquired. 

the  lower  Valley  of  the  Wye,  about  the  region  of  Tintern  Abbey,  is  a  good  illustrative 
case  in  point. 

The  way  water  companies  usually  soften  chalk-water,  is  to  add  more  lime  to  it ;  the 
carbonic  acid  takes  this  up  to  form  carbonate  of  lime,  which  is  precipitated  along  with 
the  carbonate  of  lime  previously  held  in  solution.  This  can  be  done  on  a  small  scale, 
by  strring  up  a  very  small  quantity  of  lime  with  the  water  in  the  water-butt,  taking  care 
not  to  add  more  than  enough  to  neutralize  the  carbonic  acid ;  the  whole  of  the  lime 
in  the  water  will  then  be  precipitated,  and  time  should  be  allowed  for  it  to  settle. 
Bischof,  about  the  best  authority  on  the  subject,  says  that  one  part  of  carbonate  of  lime 
dissolves  in  about  1000  parts  of  water  saturated  with  carbonic  acid.  Freseuius,  however, 
states  that  it  dissolves  in  8834  parts  of  boiling  water,  and  10,600  parts  of  cold  water,  a 
difference  from  his  own  results,  which  Bischof  remarks  that  he  cannot  explain. — W.  H. 
HARRISON. 

Water  Tests.  Test  for  Hard  or  Soft  Water. — Dissolve  a  small  quantity  of  good  soap  in 
alcohol.  Let  a  few  drops  fall  into  a  glass  of  water.  If  it  turn  milky  it  is  hard ;  if  not, 
it  is  soft.  Test  for  Earthy  Matters  in  Alkali. — Take  litmus  paper  dipped  in  vinegar,  and 
if,  on  immersion,  the  paper  returns  to  its  true  shade,  the  water  does  not  contain  earthy 
matter  or  alkali.  If  a  few  drops  of  syrup  be  added  to  a  water  containing  an  earthy 
matter,  it  will  turn  green.  Test  for  Carbonic  Acid. — Take  equal  parts  of  water  and 
clear  lime  water.  If  combined  or  free  carbonic  acid  is  present  a  precipitate  is  seen,  to 
which,  if  a  few  drops  of  muriatic  acid  be  added,  an  effervescence  commences.  Test  for 
Magnesia. — Boil  the  water  to  a  twentieth  part  of  its  weight,  and  then  drop  a  few  grains 
of  neutral  carbonate  of  ammonia  into  a  glass  of  it,  and  a  few  drops  of  phosphate  of  soda. 
If  magnesia  be  present,  it  will  fall  to  the  bottom.  Tests  for  Iron. — 1.  Boil  a  little  nut- 
gall  and  add  to  the  water.  If  it  turns  gray  or  slate-black,  iron  is  present.  2.  Dissolve 
a  little  prussiate  of  potash,  and  if  iron  is  present  it  will  turn  blue.  Test  for  Lime. — Into 
a  glass  of  water  put  two  drops  of  oxalic  acid  and  blow  upon  it;  if  it  gets  milky,  lime  is 
present.  Test  for  Add. — Take  a  piece  of  litmus  paper.  If  it  turns  red,  there  must  be 
acid.  If  it  precipitates  on  adding  lime  water,  it  is  carbonic  acid.  If  a  blue  sugar  paper 
is  turned  red,  it  is  a  mineral  acid. — Public  Opinion,  London. 

117.  In  the  course  of  conversation  with  photographers  having  a  large  staff  of  opera- 
tors, printers,  etc.,  they  have  not  infrequently  complained  to  us  of  the  irregular  results 
that  were  sometimes  observed  in  a  day's  work,  both  in  the  operating-room  and  the  print- 
ing department;  while,  among  those  amateurs  whose  time  for  photographing  is  limited 
to  an  occasional  afternoon,  the  most  common  complaint  is  the  uncertainty  of  processes  in 
their  hands.  But  this  need  not,  and  should  not  be.  In  an  important  branch  of  science, 
looking  at  photography  from  its  physical  aspect,  for  the  results  to  be  uncertain,  and  the 


CONCERNING    CHEMICALS.  249 

Chemicals  sometimes  seem  to  be  like  human  beings.  We  have  many  of  us 
been  employed  by  others.  In  photography  especially,  we  know  how  much 
more  satisfaction  there  is  in  laboring  for  a  man  who  understands  the  art  him- 
self — who  is  master  of  it  in  every  detail — and,  therefore,  though  very  exacting, 
he  understands  and  appreciates  our  efforts  better.  The  chemicals  seem  to  feel 

exact  conditions  governing  them  to  be  unknown  or  neglected,  is  most  unworkmanlike, 
and  can  have  no  other  tendency  than  to  degrade  the  importance  of  photography  in  the 
eyes  of  scientific  workers  generally. 

The  vast  progress  made  in  chemical  science,  for  instance,  during  the  last  few  years? 
would  never  have  been  achieved  had  no  more  attention  been  paid  to  rigid  exactitude  than 
is  commonly  given  in  the  practice  of  photography ;  neither  would  the  marvellous  com- 
mercial production  of  complicated  chemical  substances  have  arrived  at  its  present  stage 
of  magnitude  and  excellence  if  the  strictest  watch  had  not  been  kept  at  every  stage  of 
the  process  to  insure  scrupulous  attention  to  the  carrying  out  of  all  the  necessary  condi- 
tions. But  in  even  the  largest  photographic  establishments  how  rare  is  it  not  to.  find 
such  cases !  How  many  operators  and  printers  use  their  thermometers,  their  hydrome- 
ters, or  the  simplest  form  of  burette?  Rule  of  thumb  prevails  almost  universally,  with 
the  result  of  many  thousands  of  pounds'  worth  of  material  being  wasted  beyond  redemp- 
tion. True  it  is  every  one  knows  that  in  cold  weather  his  chemicals  require  strengthen- 
ing, and  that  in  hot  weather  stains  are  apt  to  occur,  and  some  little  alteration  is  made  by 
guesswork  to  bring  things  right.  , 

What  is  required,  however,  is  a  set  of  tables  for  strengths  of  various  solutions  required 
for  different  temperatures,  a  few  days'  rigid  examination  of  results  under  such  varying 
conditions  as  are  likely  to  occur,  and  such  a  tabulated  statement  of  them  as  would  enable 
each  to  alter  for  himself  the  chemicals  he  is  using,  or  know  from  their  strength  and 
temperature  the  effects  he  is  to  expect,  thus  establishing  the  routine  of  operation  on  a 
thoroughly  sound  basis. 

We  may  give  an  example  of  what  we  think  ought  to  be  possible  in  the  hands  of  an 
ordinary  and  careful  manipulator.  Every  morning  he  would  take  the  temperature  of 
his  dipping-bath,  and,  as  the  strengthening  or  weakening  of  that  solution  would  take  up 
time,  he  would  best  bring  it  to  a  uniform  temperature,  which  could  very  easily  be  done; 
but  if  time  or  circumstances  prevented  that  being  accomplished,  he  would  refer  to  his 
table,  and  find  for  a  given  temperature  what  was  the  equivalent  strength,  and  could  then 
vary  his  developer  according  to  the  table — a  definite  alteration  in  strength  of  which 
would  be  given  for,  say,  each  two  degrees  of  temperature.  Working  with  a  collodion  or 
emulsion  of  uniform  quality,  he  would  then  know  at  once  what  would  be  his  results. 
Then,  again,  every  few  days,  more  or  less,  according  to  the  greater  or  less  work  the  bath 
has  had,  he  might  test  its  strength,  and  bring  it  up  to  the  exact  strength  he  considers 
best.  And  so,  in  the  printing  department,  when  the  greatest  irregularity  usually  is  found, 
his  table  would  show  him  what  difference  in  strength  would  be  equivalent  to  a  fall  or 
rise  of  a  degree  or  two  in  temperature,  and  every  time  he  prepared  for  floating  the  paper 
he  would  bring  up  the  temperature  or  add  strong  solution  of  silver  in  cold,  or  vice  versa 
in  hot  weather.  The  effect  of  an  alteration  of  a  few  degrees  in  the  temperature  of  the 


250         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

the  same  way  sometimes.  Be  careless  with  them  and  they  will  trick  you. 
When  you  are  exacting  they  are  most  apt  to  yield  to  your  will  and  pleasure. 

With  the  purpose  of  mastering  them  in  every  detail,  let  us  now  enter  the 
mysteries  of  practical  photograph  production. 

printing  bath  is  most  marked.  So,  again,  in  making  his  gold  toning-bath;  if  he  makes 
it  of  an  acid  sample  on  one  occasion,  and  nearly  neutral  on  another,  he  must  expect  to 
find  want  of  uniformity  of  result;  but  if  he  make  his  gold  as  nearly  neutral  as  he  can 
before  adding  his  alkali  he  will  know  exactly  how  it  will  tone. 

These  remarks  are  merely  meant  to  give  what  we  might  term  the  skeleton  of  "  prac- 
tical "  modes  of  introducing  exactitude  in  all  departments,  and  the  preparation  of  such 
tables  as  we  suggest  would  only  require  very  careful  attention  and  comparison  of  results. 
One  set  of  tables  would  in  practice  suffice  for  all  photographers;  and,  when  they  were 
really  fairly  applied  in  daily  routine,  their  broad  bearings  would  be  thus  learned  by  heart 
to  an  extent  far  more  exact  than  the  practical  knowledge  of  even  the  most  experienced 
operator — so  much  so  that  it  would  only  be  when  results  of  especial  exactitude  were 
required  that  anything  like  "  calculation  " — the  bugbear  of  the  rule-of- thumb  manipu- 
lator— would  be  needed. — AN  ENGLISH  PHOTOGRAPHER. 


CHAPTER   XIII. 

DARK-ROOM   CONTRIVANCES. 

118.  As  a  rule  the  dark-room  is  constructed  on  too  small  a  scale.  It  should 
be  roomy ;  arranged  so  it  could  be  thrown  open  daily,  and  the  air  allowed  to 
circulate  freely  through  all  its  parts ;  well  lighted  and  supplied  with  every 
convenience.  And  to  entirely  suit  the  emulsion  process  there  should  be  an 
annex  or  secondary  dark-room,  where  the  stock  of  dry  plates  may  be  stored, 
holders  changed,  in  case  the  dark-room  proper  is  being  aired,  and  where  the 
over-supply  of  chemicals  may  be  stored,  so  as  to  do  away  with  shelves  in  the 
larger  room  as  much  as  possible.  I  will  offer  some  suggestions  as  to  a  model. 

It  is  an  old  "  wet  plate  "  room  "  made  over,"  we  will  say,  and  as  will  be 

118.  The  sink  I  use  in  the  dark-room,  with  a  view  of  saving  some  of  the  silver  usually 
lost  during  the  development  of  negatives,  is  made  thus: 

It  consists  of  a  box  of  wood,  one  side  (which  when  in  use  forms  the  back)  of  which  is 
upright,  while  the  other  three  slope  inwards  toward  the  bottom,  forming  a  sort  of  square 
funnel.  This  is  lined  with  lead  in  the  usual 
manner.  The  neck  is  formed  by  a  piece  of 
lead  or  brass  tubing,  about  six  inches  long 
and  one  and  a  half  inch  diameter,  and  which 
is  stopped  at  the  bottom.  Into  this  is  in- 
serted a  sort  of  double  stopcock,  the  plug  of 
which  is  so  bored  that  when  one  tube  is  open, 
the  other  is  shut.  These  taps  are  firmly  at- 
tached by  means  of  an  iron  rod  to  the  lower 
part  of  the  tap  used  to  regulate  the  supply 
of  water  over  the  sink ;  and  are  so  arranged 
that  when  the  water  is  turned  on  into  the 
sink  that  portion  of  the  stopcock  leading  to 
the  water  is  turned  on  also,  while  that  lead- 
ing to  the  vessels  containing  the  silver  solu- 
tion is  turned  off,  thus  allowing  the  water 
used  in  washing  to  flow  away.  The  simple 
act  of  turning  off  the  water  supply  at  once  turning  off  the  escape  pipe,  and  opening  that 
leading  to  the  reservoir  containing  the  solutions  which,  of  course,  remains  open  until 
the  water  is  again  turned  on  for  washing  the  plates. 

(251) 


252        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


FIG.  243. 


seeri  by  the  dimensions  given,  is  suited  for  a  moderate  business.     It  is  roomy, 
amply  lighted,  and  well  arranged.     A  drawing  will  help.     The  dark-room  is 

at  the  northwest  corner  of  the  studio, 
convenient  to  the  operator  and  yet  out 
of  the  way.  Entering  the  room  we  find 
on  the  left,  or  west  side,  1,  a  dumb- 
waiter, communicating  with  the  work- 
room on  the  ground-floor;  2,  a  small 
closet,  used  for  filtering  apparatus  for 
the  bath  ;  3,  is  the  negative  bath  ;  4,  is 
a  window  with  ruby  glass,  covered  with 
a  yellow  curtain,  and  also  furnished 
with  a  dark  opaque  curtain  sliding  on  a 
rod,  so  that  the  room  may  be  made  very 
dark  or  moderately  so,  at  will.  At  the 

north  end  of  the  room  are  three  tanks 

> 

viz.:  5,  30  inches  square,  by  12  inches 
deep,  for  developing  and  first  washings ;  6,  30  inches  wide,  47  inches  long,  6 
inches  deep,  for  final  washing  of  the  negatives;  and  7,  20  inches  x  24  inches, 
and  3  inches  deep,  situated  on  a  stand  18  inches  over  No.  6,  as  will  be  seen  in 
the  drawing,  used  for  fixing  the  negatives. 

No.  5  is  always  kept  half  full  of  water,  and  instead  of  having  a  waste-pipe 
merely,  has  an  outlet  through  the  floor  of  the  room,  down  to  a  barrel  on  the 
lower  floor,  which  catches  the  waste  solution.  (This  waste  solution  after 
standing  over  night,  in  order  to  allow  the  silver  to  subside,  is  then  drawn  off 
every  morning.)  The  fixing  bath,  by  being  smaller  than  and  over  the  washing 

If  we  now  proceed  to  develop  a  plate,  the  overflow  of  the  developing  solution  at  once 
flows  down  the  tube  into  the  reservoir,  and  is  saved;  as  is  also  the  solution  drained  off 
on  the  completion  of  the  development.  Then  the  waste  being  turned  on,  the  opening  to 
the  reservoir  is  closed,  while  that  to  the  waste  is  opened,  and  the  water  flows  freely 
away.  For  intensifying  (and  also  for  fixing,  should  cyanide  be  used),  the  same  operation 
is  gone  through,  and  the  solutions  are  thus  saved  without  any  trouble  or  loss  of  time  to 
the  operator. 

A  sink  of  this  form  possesses  also  the  following  advantages:  first,  there  is  no  splashing, 
on  account  of  the  sloping  sides  upon  which  the  water  falls ;  and,  secondly,  that  as  the 
sink  is  kept  drained,  and  is,  in  fact,  washed  out  in  the  act  of  washing  each  plate,  no 
injurious  fumes  are  likely  to  arise  to  cause  the  ill  health  of  the  operator,  as  in  the  old 
form  of  sink,  when  the  solutions  were  allowed  to  mix  freely  in  an  open  vessel  which  was 
never  perfectly  freed  from  them. — J.  C.  LEAKE. 


DARK   ROOM    CONTRIVANCES. 


253 


FIG.  244. 


tank,  and  eighteen  inches  above  it,  permits  the  negatives  to  be  taken  out,  and 
the  droppings  to  fall  into  the  washing  tank,  thus  avoiding  droppings  of  hypo 
on  the  floor.  The  developing  tank  is  supplied  with  one  faucet,  and  the  wash- 
ing tank  with  two. 

119.  On  the  east  side  is  a  table  (8)  on  which  are  kept  the  plate  holders. 
Between  this  table  and  the  tanks  5,  6,  and  7,  is  a  long  tank  for  plate-washing, 
12  inches  deep  and  5  feet  long;  an  inclined  false  bottom  reaches  from  end  to 
end,  within  5  inches  of  the  top  at  the  back,  inclining  to  the  bottom  at  the  front 
edge.  Along  the  whole  length  is  a  perforated  water  pipe  which  casts  a  con- 
tinuous stream  over  the  plates  as  they  He  one  above  the  other,  edge  to  edge  on 
the  inclined  plane.  Thus  many  plates  may  be  washed  at  one  time. 

Over  the  tanks  are  nails  to  hang  the  negatives  upon.  All  parts  are  painted. 
The  floor  is  covered  with  brown  oil-cloth ;  wiped  with  a  damp  cloth  daily,  and 
never  swept.  The  walls  are  painted.  No  superfluities  are  allowed  in  the 

For  washing  two  negatives  at  once  from  one  faucet,  a  x  shaped  instrument  is  made  of 
tin.  The  horizontal  part  is  nearly  flat,  and  is  pierced  with  small  holes  like  those  of  a 
rose  on  the  under  side,  at  each  end,  not  in 
the  middle  part.  The  vertical  part,  A,  is  a 
tube,  about  an  inch  in  diameter,  which  is 
fitted  by  means  of  a  cork,  B,  to  the  water- 
faucet.  The  water  being  turned  on,  a  gentle 
stream  runs  from  each  extremity  of  the  hori- 
zontal tube.  The  arrangement,  C,  D,  repre- 
sented beneath,  is  independent  of  the  upper, 
and  is  very  convenient  for  any  negative 
washing.  C  is  a  tin  funnel  without  any 
neck,  and  with  sides  sloping  very  gradually. 
It  enters  about  half  way  into  a  large  tum- 
bler, or  glass  jar,  D.  (The  large  heavy  tum- 
blers made  for  cells  for  large-sized  Grove's 
batteries  are  very  suitable,  and  are  what  I 
use.)  If  now  a  negative  be  rested  upon  the 
upper  part  of  the  tin  funnel,  it  will  be  found 
easy  to  arrange  it  so  as  to  incline  to  any  degree,  and  in  any  direction ;  and  it  will  remain 
during  washing  steadily  in  that  position,  without  shifting.  The  operator  obtains  without 
any  difficulty  such  an  inclination  that  the  water  falls  on  one  end,  and  passes  off  at  the 
other  and  at  the  same  time  keeps  up  a  tremulous  sheet  over  the  whole  surface. — M. 
CAREY  LEA. 

119.  The  annexed  sectional  diagram  illustrates  a  simple  but  very  efficient  ventilator, 
which  may  be  easily  fitted  to  any  existing  dark-room,  with  very  little  trouble  or  expense. 


254 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  245. 


room.  Its  size  is  16  feet  wide  east  to  west,  by  14  feet  long  north  to  south. 
The  tanks  across  the  end  of  the  room  occupy  three  feet,  leaving  a  very  com- 
fortable amount  of  space  to  work  in.  It  is  ventilated  by  an  aperture  through 
the  ceiling  and  roof,  and  by  the  dumb-waiter,  the  mouth  of  which  latter  is 
level  with  the  floor. 

120.  Between  the  dark-room  and  the  annex  is  an  entry  three  feet  wide,  with 

I  have  long  had  these  "air-holes"  attached  to  my  dark-room,  and  can  vouch  for  their 
utility. 

It  is  advisable  to  fix  one  at  each  end  of  the  room ;  the  first  near  the  floor,  preferably 
under  the  sink,  for  the  inlet  of  fresh  air,  the  other  near  the  roof, 
for  the  outlet  of  exhausted  or  heated  air. 

A  horizontal  opening  is  cut  in  the  wall  (A]  (which  in  England, 
almost  invariably,  is  constructed  of  wood),  from  12  to  24  inches  in 
length,  and  3  or  4  inches  deep.  Directly  over  the  opening,  at  each 
side  of  the  partition,  is  fastened  a  strip  of  wood  (B]  an  inch  or 
more  thick,  about  2  inches  wide,  and  the  length  of  the  opening. 
To  these  strips  are  screwed  boards  ( C]  not  less  than  a  foot  wide. 
All  that  now  remains  to  be  done  is  to  fix  strips  at  each  end,  so  that 
the  air  and  light  can  only  enter  at  the  bottom,  the  former  fol- 
lowing the  direction  of  the  arrows,  while  the  light  finds  some  little 
difficulty  in  turning  the  corners.  Dust  may  be  entirely  excluded 
by  glueing  over  the  opening,  at  the  inside,  a  piece  of  fine  gauze. — 
C.  C.  VEVERS. 

The  greater  part  of  the  chemicals  used  in  photography  throw  off 
poisonous  fumes  when  exposed  to  the  atmosphere.  The  dark-room 
is  generally  the  receptacle  for  these  articles  and  where  they  are 
most  used.  Therefore,  it  should  be  well  ventilated.  I  have  made 
two  boxes  two  feet  square,  outside  measure,  and  open  at  both  ends. 
Have  made  three  light  partitions,  two  extending  from  one  side 
six  inches  from  either  end,  and  twelve  inches  apart,  extending 
to  within  six  inches  of  the  opposite  side.  Now  from  this  oppo- 
site side  and  exactly  between  the  two  put  another  partition,  extending  to  within  six 
inches  of  the  side  to  which  the  first  two  were  attached.  The  partitions  will  be  best  fast- 
ened to  the  two  opposite  sides  before  putting  the  box  together,  but  it  is  easier  to  explain 
it  as  I  have  attempted  to  do.  Next  fit  the  boxes  in  two  openings  cut  at  opposite  points 
and  next  to  the  ceiling  of  your  dark-room.  Put  the  boxes  in  so  that  the  air  passes  out 
at  the  upper  side,  as  it  is  safest  against  defects  or  strong  light  this  way. — M.  L.  COBMANY. 
120.  In  the  arrangement  of  large  plates  in  the  dark  room  it  will  be  found  convenient 
to  have  the  light  so  arranged  that  a  negative  may  be  examined  by  transmitted  light 
while  developing,  without  handling  it  or  the  developing  dish. 

For  this  purpose  the  light  must  be  one-half  above,  and  one-half  below  a  skeleton 
shelf,  and  the  developing  dish  must  have  a  glass  bottom.     Let  the  light  be,  say,  twenty 


DARK-ROOM    CONTRIVANCES.  255 

a  window  opening  to  the  daylight,  and  glazed  with  ruby  colored  glass.  This 
lights  both  rooms.  On  very  dark  days  the  gas  is  lighted  in  the  entry. 

inches  square  above,  and  twenty  inches  square  below  the  shelf.  Now  make  two  curtains 
of  heavy  paper  twenty  inches  square,  and  supply  them  with  sticks  at  the  top  and  bottom. 
Hang  the  one  above  the  light  by  means  of  a  cord  pulley  and  balance  weight,  and  sus- 
pend the  other  from  the  bottom  of  the  upper  curtain,  so  that  there  is  a  space  of  twenty 
inches  between  them.  When  you  raise  them,  the  light  will  be  clear  above  the  shelf,  and 
when  you  lower  them  the  light  will  be  open  below  and  closed  above,  and  you  can  examine 
your  negative  at  leisure. — F.  B.  ZAY. 

I  would  call  attention  to  the  value  of  bichromate  of  potash  solution  for  dark  room 
use.  By  it  we  can  obtain  an  excellent  illumination,  and  at  the  same  time  it  is  very 
effective  in  stopping  out  chemical  rays.  Four  years'  experience  in  its  use  has  confirmed 
my  first  impression  as  to  its  utility ;  but  I  can  now  give  some  further  hints  that  may  be 
useful. 

In  the  first  place,  it  is  well,  as  involving  less  trouble  and  expense,  to  depend  upon 
yellow  paper,  as  heretofore,  for  the  general  lighting  of  the  room,  that  is  when  a  window 
of  sufficient  size  is  available ;  but  to  have  some  means  of  darkening  this  readily,  when 
danger  of  fogging  is  apprehended.  Then  immediately  opposite,  and  as  near  as  possible 
to  the  place  it  is  most  convenient  to  hold  the  plate  while  developing,  have  one  or  two 
common  cylindrical  quart  bottles  filled  with  half-saturated  solution ;  each  should  stand 
upon  a  small  circular  shelf  with  raised  edge,  placed  at  the  bottom  of  an  opening  in  a 
thin  board  partition. — JOHN  M.  BLAKE.  . 

In  this  connection  may  be  mentioned  a  device  which  has  proved  very  useful  as  an 
auxiliary  in  enabling  one  to  judge  of  the  proper  development  of  a  negative  A  square 
hole  measuring  an  inch  and  a  half  on  a  side,  is  cut  in  the  upper  portion  of  the  golden 
fabric,  and  a  piece  of  red  glass  inserted  between  the  two  thicknesses.  If  a  negative  be 
now  held  near  this  hole,  a  red  square  of  light  will  be  cast  upon  it.  This  square  can  be 
seen  even  when  the  lights  of  the  negative  are  quite  intense,  and  by  noting  its  distinct- 
ness, one  can  judge  of  the  opacity  of  the  high  lights  as  accurately  as  he  can  of  the  details 
of  the  shadows  of  the  picture.  If  the  high  lights  reach  their  proper  intensity  first,  he 
develops  for  the  shadows,  and  vice  versa. 

As  the  whole  question  of  the  proper  medium  to  use,  resolves  itself  merely  into  what 
part  of  the  spectrum  to  employ,  red,  orange,  or  orange-yellow,  and  all  three  of  these 
yield  nearly  equally  good  results,  it  is  evident  that  no  important  improvement  can  be 
made  in  the  future.  But  as  the  orange-yellow  is  much  the  more  pleasant  light  of  the 
three,  and  seems  to  give  rather  less  fog  than  either  of  the  others,  it  is  the  color  to  be 
recommended.  Any  medium  which  will  transmit  this  color  will  be  found  satisfactory, 
but  golden  fabric  is,  perhaps,  as  convenient  as  any. 

A  very  portable  form  of  lantern  to  be  used  when  travelling,  consists  of  a  strip  of 
golden  fabric  a  foot  wide  by  two  and  a  half  in  length.  When  one  wishes  to  use  it,  it  is 
rolled  into  a  cylinder  a  foot  long,  and  five  inches  in  diameter,  and  pinned.  A  kerosene 
lamp  with  the  wick  turned  down  low,  or  a  candle,  is  then  placed  inside,  and  the  lantern 
is  complete.  The  circle  of  white  light  formed  on  the  ceiling  is  not  bright  enough  to  do 


256         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  communication  between  the  rooms  is  by  means  of  a  door  at  the  inside 
end  of  the  entry.  The  holders,  etc.,  are  passed  through  the  windows  opening 
upon  the  entry. 

any  harm.  The  lantern  is  set  several  feet  away  from  the  exposed  plates,  and  they  should 
in  general  be  protected  as  much  as  possible  from  direct  illumination.  There  is  then 
plenty  of  light,  and  yet  not  the  slightest  danger  of  fog. — WM.  H.  PICKERING. 

Notwithstanding  the  old  writers,  there  are  but  three  primary  colors — red,  yellow,  and 
blue.  We  know  that  these,  and  these  only,  are  primary,  because  no  admixture  of  any 
other  colors  will  produce  them,  which  is  not  the  case  with  the  rest ;  for  orange  is  only  a 
mixture  of  red  and  yellow,  green  is  only  the  shading  of  yellow  into  blue,  and  purple  is 
only  blue  blending  into  red.  Now,  as  the  last  primary  color  in  the  spectrum  is  seen  to 
join  with  the  first  in  the  production  of  the  intermediate  shade  of  purple,  or  violet,  as  it  is 
usually  called,  we  may  with  propriety  curl  the  spectrum  into  a  circle,  in  order  to  repre- 
sent to  the  eye  the  inter  relation  of  the  triad  of  primary  colors.  In  the  annexed  diagram 
let  the  capital  letters,  R,  Y,  B,  represent  the  primary  colors,  and  the  small  letters,  o,  g,  v, 

the  compound  colors.  Now,  it  is  natural  to  infer  that  if 
we  establish  a  certain  quality  as  belonging  to  a  certain 
color,  when  we  seek  for  the  direct  opposite  of  this  quality 
we  should  look  for  it  not  in  any  near  color  but  in  the  op- 
posite side  of  the  spectrum  thus  returning  into  itself.  It 
would  take  too  much  space  to  illustrate  this  at  length,  but 
a  very  pleasing  method  of  testing  the  compleniental  colors 
is  to  fill  the  eye  for  some  minutes  with  some  strongly 
marked  colored  light,  and  then  retire  into  the  dark  and 
observe  the  tint  of  the  image  presented  to  the  optic  nerves. 
If  we  have  been  looking  at  a  pure  red  light  we  shall  in 
the  dark  see  a  green  image ;  if  at  yellow,  we  shall  see 
violet,  etc. ;  these  colors,  respectively,  being  on  opposite 
sides  of  the  sprectrum,  as  drawn  in  our  diagram. 

Pure  blue,  or,  possibly,  blue  slightly  tending  to  violet,  is  known  to  embrace  most  of 
the  chemical  rays.  Hence,  to  find  what  rays  will  operate  the  least  on  our  plates,  we 
look  to  the  opposite  or  complemental  color,  orange,  and  are  not  disappointed.  But, 
whatever  may  be  thought  of  the  theory,  the  fact  is,  briefly,  we  are  now  developing  our 
dry-plates  in  front  of  nine  8  x  10  orange  lights,  set  back  about  eight  feet  from  a  good- 
sized  outside  window,  and  admitting  light  enough  for  one  to  read  the  finest  newspaper 
type  on  a  dark  day.  It  must  be  understood  that  the  darker  shade  of  photographers' 
yellow  glass  is  to  be  selected,  not  the  canary,  nor  yet  the  very  brown.  Strictly  speaking, 
very  little  of  this  glass  is  orange — as  it  should  be — but  it  is  near  enough  to  that  color. 

The  pleasure  of  working  in  an  agreeable  light,  and  plenty  of  it,  will,  we  are  sure,  be 
appreciated  by  all  our  readers,  and  we  urge  them,  after  they  have  satisfied  themselves, 
cautiously,  that  we  are  right,  to  save  their  eyes. — WILLIAM  CURTIS  TAYLOR. 

I  give  you  herewith  my  process  for  the  automatic  development  of  gelatine-bromide- 
negatives,  giving  a  coloration  as  intense  as  may  be  desired. 


DARK-ROOM    CONTRIVANCES.  257 

Where  there  is  abundance  of  room  and  daylight  is  not  convenient,  it  is  a 
good  plan  to  have  a  table  in  the  centre  of  the  room,  and  on  it  a  huge  ruby- 
colored  lantern,  lighted  by  gas  or  kerosene.  A  generous  supply  of  light,  well 
diifused,  may  be  secured  in  this  way,  and  no  harm  done,  provided  the  color  is 
right.  Care  and  judgment  is  all  that  is  necessary  in  a  photographer  to  over- 
come whatever  difficulties  may  arise. 

121.  I  need  not  caution  the  photographer  of  to-day  to  be  careful  not  to  use 

Eed  light,  being  the  one  having  less  chemical  action  on  bromide  of  silver,  and  good 
red  glass  being  expensive,  here  is  a  way  to  obtain  it  at  very  little  expense.  The  window 
of  the  dark  room,  glazed  with  ordinary  white  glass,  for  an  opening  measuring  1£  yards 
of  surface,  dissolve  5  grammes  (77  grains)  of  carmine  in  40  grammes  (1  oz.  2  drs.)  of 
liquid  ammonia.  On  the  other  hand,  dissolve  2  grammes  (31  grains)  of  picric  acid  in 
450  grammes  (14  ozs.  3  drs.)  of  water,  to  which  7  grammes  (2  drs.)  of  glycerine  have 
been  added ;  introduce  into  this  yellow  water  50  grammes  (1  oz.  5  drs.)  of  gelatine,  which 
is  allowed  to  swell  for  an  hour,  and  then  dissolved  over  a  water  bath.  When  the  gelatine 
is  melted,  the  ammoniacal  carmine  coloring  is  carefully  added  to  it,  and  kept  hot  over  a 
water  bath ;  this  mixture  is  spread  with  a  flat  brush  over  the  glass.  As  soon  as  the  first 
coat  of  the  colored  gelatine  is  sufficiently  set,  it  may  be  covered  with  a  second,  and  then 
a  third  coat ;  by  this  means  it  is  possible  to  obtain  a  coloration  as  intense  as  may  be 
wished. 

In  order  that  this  brilliant  red  light  should  not  fatigue  the  operator's  eyes,  place  before 
the  glass,  instead  of  curtains,  two  strips  of  yellow  paper,  and  the  light  of  the  dark  room 
will  then  be  in  the  -best  possible  condition. — M.  CASSAN.  • 

121.  Last  winter  I  began  to  be  troubled  with  minute  black  specks  being  deposited  all 
over  the  albumenized  surface  of  my  paper  while  washing  my  prints  before  toning,  and 
could  not  discover  at  the  time  the  cause.  I  inquired  from  a  number  of  photographers 
in  regard  to  my  trouble,  and  all  seemed  to  agree  that  it  was  the  paper,  so  I  procured  a 
sample  of  two  or  three  different  makes  of  paper,  and  still  the  same  trouble.  The  paper 
appeared  to  be  clear  when  printing,  but  after  washing  was  full  of  those  black  specks, 
which,  on  rolling  after  being  mounted,  would  have  a  metallic  appearance.  I  began  to 
get  very  much  discouraged,  having  made  different  silvering  solutions,  but  still  the  same 
result,  when  at  last  I  thought  I  would  silver  a  piece  of  paper  and  not  print  it,  but  after  dry- 
ing place  it  in  a  porcelain-dish.  Leaving  plenty  of  light  in  my  room,  I  drew  some  water 
directly  on  it  from  the  tap,  and  by  examining  closely  I  could  see  small  particles  deposit- 
ing all  over  the  surface,  which  on  examination  proved  to  be  iron-rust,  having  been 
loosened  from  the  inside  of  a  short  piece  of  iron  pipe  by  the  frost  over  night,  the  moist- 
ure in  the  pipes  freezing  after  the  water  was  turned  off.  I  caught  and  filtered  some  of 
the  water,  and  was  satisfied  from  the  deposit  on  the  filter  that  I  had  found  the  cause  of 
my  trouble. — J.  B.  BUTTERFIELD. 

I  have  found  a  successful,  neat,  and  durable  bath-tub  can  be  made  at  trifling  expense, 
as  follows :  Make  a  box  of  wood,  seasoned,  of  the  size  you  desire.  I  would  make  it  a 

17 


258         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

metal  pipes  or  vessels  of  any  kind,  which  may  contaminate  his  chemicals.  To 
prevent  such  misfortune  and  leakage  too,  the  tanks  should  be  lined  with 
asphaltum  varnish,  beeswax,  or  paraffine.  A  hint  as  to  preparing  substances 
for  this  purpose.  Do  not  melt  them  at  too  great  a  heat.  If  you  do,  they 
become  hard  or  brittle  when  cold,  and  are  liable  to  crackle  off,  fall  into  the 
solutions,  cause  contamination,  and  fail  of  their  purpose.  Use  slow  heat ;  melt 
to. the  consistence  of  tar,  and  apply  with  a  flat  bristle  varnish  brush.  The 
more  coats  the  better.  Sometimes  a  coating  of  vaseline  is  better  than  nothing 
at  all. 

little  flaring  or  V-shaped,  say  three-quarters  of  an  inch  wider  at  the  top  than  at  the 
bottom.  It  must  be  tight. 

Next,  have  made  of  tin  or  zinc,  what  moulders  would  call  a  core,  to  fit  the  shape  of 
the  wooden  box,  only  about  one-half  inch  less  than  the  inside  of  wooden  box  all  around. 
This  core  you  will  fasten  or  anchor  by  soldering  double-seamed  strips  across  the  top,  and 
let  the  ends  be  tacked  to  the  wooden  box.  Now  you  see  that  the  tin  core  is  suspended 
inside  of  the  wooden  box  with  a  space  all  round  and  at  the  bottom.  Now  get  you  a  suffi- 
cient quantity  of  pure  country  beeswax,  melt  it,  and  pour  around  the  core  into  wooden 
box ;  watch  it  carefully,  and  as  it  settles,  fill  up  with  more  wax.  Now,  you  see,  you 
have  a  beeswax  bath-tub  with  a  tin  lining.  You  don't  like  this?  Well,  take  enough  hot 
water  to  fill  the  tin  core,  first  loosening  the  tacks  holding  the  strips ;  lift  quickly  out  of 
its  place,  and  let  it  cool  perfectly ;  if  any  asperities  appear,  shave  them  off.  You  now 
have  a  permanent,  impermeable,  insoluble,  chemical-defying  bath-tub.  It  will  not  open 
by  shrinking  or  swelling  of  the  wood.  I  would  recommend  a  light  coating  of  tallow 
inside  of  the  wooden  box  to  obviate  sticking,  if  the  wood  should  shrink,  as  will  almost 
surely  be  the  case  after  some  use.  Let  it  cool  thoroughly  before  taking  the  core  out. 
Pour  the  wax  as  cool  as  it  will  run. — A.  R.  C. 

"  I  think  paraffine  can  be  of  great  use  to  photographers.  Nothing  surpasses  it  to  coat 
wooden  dishes  with.  I  prefer  such  dishes  to  hard  rubber,  porcelain,  or  photographic 
ware.  A  good  coating  of  paraffine  for  the  inside,  and  two  or  three  of  white-lead  paint  on 
the  outside,  will  make  a  wooden  dish  perfectly  watertight.  A  very  good  silver  bath- 
holder  may  be  made  in  the  same  way.  The  dish  or  bath  is  well  warmed,  the  molten 
paraffine  poured  into  it  and  made  to  move  all  over  the  inside  surface.  Then,  if  possible, 
if  the  vessel  be  put  into  an  oven  just  hot  enough  to  keep  the  paraffine  melted,  it  will 
penetrate  more  deeply  in  the  wood  and  improve  its  water-tight  qualities.  Plate-holders 
made  of  wood,  without  glass  or  composition  corners,  by  being  put  in  the  molten  paraffine, 
will  forever  after  refuse  to  absorb  the  silver,  and  will  never  produce  stains.  Manufac- 
turers of  camera  boxes  would  do  well  to  consider  this,  and  all  of  the  wood-work  of  the 
camera  boxes  would  be  improved  by  immersion  in  this  useful  protection.  A  camera- 
box  made  of  dry  wood,  as  it  should  be,  and  well  coated  in  this  way,  would  never  warp  or 
corrode  by  the  nitrate  of  silver.  In  coating  an  object,  it  should  be  observed  that  the 
hotter  the  paraffine  the  more  perfectly  will  it  penetrate  the  wood. — CHARLES  WALDACK. 


DARK-ROOM    CONTRIVANCES. 


259 


122.  Allusion  has  been  made  to  the  importance  of  keeping  the  working 
solutions  of  a  uniform  temperature.  In  some  buildings  this  is  almost  an 
impossibility  in  winter,  while  in  summer  the  great  trial  is  to  prevent  too  high 
a  temperature.  Ventilation  is  also  a  subject  which  cannot  be  given  too  much 
attention,  not  only  as  a  matter  of  health,  but  as  help  towards  maintain- 
ing a  uniform  temperature.  A  clear  atmosphere  is  by  no  means  always  the 
coolest  one. 

What  I  want  to  make  the  clearest,  however,  is  the  importance  of  keeping 
the  various  solutions  at  the  proper  temperature  and  to  have  them  all,  as  nearly 
as  practicable,  the  same. 

Many  devices  have  been  offered  as  helpers,  some  few  of  which  are  added  to 
the  notes. 

122.  I  send  models  of  contrivances  for  cooling  the  bath,  and  for  keeping  collodion  and 
other  solutions  cool  and  of  equable  temperature  during  hot  weather.  Fig.  247  repre- 
sents the  bath  cooler,  which  is  a  simple  box 
or  case  A,  so  contrived,  with  a  metal  case 
inside,  and  outlet  for  water,  as  to  hold  lumps 
of  ice  underneath  and  over  the  glass  bath- 
holder. 

Fia.  247. 


Fio.  248. 


Fig.  248  is  the  closet  or  receptacle  for 
keeping  collodion,  developer,  etc.,  cool,  and 
divided  into  the  ice-box  A;  a,  receptacle  for 
bottles  and  vials,  B ;  an  outlet,  C,  through 
which  the  drip  flows  into  the  vessel  D,  and 
the  door  E.  Shelves  are  provided  here  and 

there  for  vials,  etc.  The  size  may  suit  the  convenience  of  the  user.  This  method  of 
using  ice  for  the  purposes  named,  is  a  good  one,  and  will  prove  a  boon  to  many  who 
have  not  thought  of  it. — SAMUEL  BOOT. 

First,  my  lamp  for  heating  the  burnisher ;  I  give  you  an  end  and  side  view  (Fig.  249). 


260 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


If  lamps  are  used  in  a  dark-room  the  subject  of  ventilation,  and  clear,  clean 
air  becomes  all  the  more  important. 


It  is  made  of  tin,  with  double  flame,  and  a  space  between  for  the  burnishing  tool, 
explains  itself  further. 

FIG.  249.  FIG.  250. 


It 


FIG.  251. 


My  chimney  attachment  for  heating  purposes,  is  also  made 

plain  by  Fig.  249. 
I  use  any  size  of  lamp  to  suit  my  purposes,  and  make  the 

attachments  of  sheet-iron.    One  for  heating  the  burnisher  can 

be  constructed  in  the  same  way,  by  using  two  four-inch  wicks, 

both  running  lengthwise  of  the  burnishing  tool. 
I  find  both  of  these  of  great  convenience  and  use  to  me  at  all  times  of  the  year. — S.  L. 

PLATT. 

The  arrangement  described  and  illustrated  below,  will  serve  an  excellent  purpose.    By 

it  the  baths  are  not  only  protected  from  accident,  but  a  constant  gentle  warmth  is 

secured  at  a  very  moderate  outlay  of  trouble 
and  coal  oil.  Developing  and  fixing  solu- 
tions may  be  kept  alike  warm,  so  that  no 
matter  how  cold  the  room,  all  things  are  in 
good  working  order,  as  far  as  temperature  is 
concerned,  as  soon  as  the  doors  are  opened 
in  the  morning.  In  the  summer  time,  a 
dish  of  ice,  instead  of  a  lamp,  will  keep  all 
cool. 

The  apparatus  may  be  cheaply  and  easily 
made,  consisting  only  of  a  wooden  box  on 
feet,  with  folding  doors,  a  support  for  the 
bath-holders,  and  a  cover.  L  is  a  coal -oil 
lamp,  placed  under  the  box,  the  chimney 
running  up  through  a  piece  of  iron  or  tin, 

at  T.    D  D  are  the  doors.    When  the  latter  are  closed,  a  very  small  flame  will  create  an 

amount  of  heat  quite  sufficient  for  the  desired  purpose.    The  box  should  be  made  of  light 

wood,  and  of  a  size  to  suit  the  requirements  of  the  operant. — E.  LONG. 


DARK-ROOM    CONTRIVANCES. 


261 


FIG.  252. 


I  have  known  photographers  to  keep  their  dark-rooms  insufferably  hot  and 
close  while  their  supply  pipes  in  winter  ran  up  from  the  ground  outside. 

I  send  you  a  diagram  of  the  way  in  which  I  have  arranged  my  waste  water  pipe,  as  I 
have  always  been  bothered  in  the  winter  season  by  having  the  pipes  frozen  up,  but  my 
plan  now  works  to  perfection,  and  is  as  fol- 
lows: A  is  the  tap  over  the  sink;  B  the 
sink ;  C  is  a  stop-cock  which  will  hold  the 
water  in  the  sink  until  it  is  full ;  then  I  let 
it  out  at  once  and  then  turn  the  stop  again ; 
D  is  a  nut  which  may  be  removed  in  case 
the  pipe  should  get  clogged  up  with  dirt  or 
lint ;  a  long  wire  may  be  run  through  from 
D  to  push  away  any  dirt.  My  waste  is  a 
three-quarter  inch  gas-pipe,  and  works  to  a 
charm.— T.  M.  WELLS. 

I  gladly  illustrate  my  method  of  keeping 
solutions  cool  in  hot  weather  by  a  drawing. 
I  have  built  permanently,  in  the  proper  place  in  the  dark-room,  a  box  in  two  sections,  a 
small  upper  section,  and  a  lower  and  larger  section,  substantially  as  shown  in  the  draw- 

FIG.  253. 


\  \\     r 

\  11x14  \\  ,-- 


\                            \' 

\        17*20 

\Door  E 

B 

\    '             d 

]  \\f:?. 

A  \ 

1  '>  \      '     ! 

\ 

I^LCfl'UQLi     jf 

THEf 

\ 

i   \\i  ij 

H 

o 


ing.  The  bottom  of  the  upper  section  is  completely  perforated  with  holes  an  inch  or 
more  in  diameter,  through  which  the  cold  air  from  the  upper  section  can  pass  down  to 
the  lower  section ;  also,  the  warm  air  from  the  lower  section  rise  to  the  upper  section  to 
become  cooled  by  the  ice  (Fig.  253). 

I  have  a  pail  made  in  two  sections,  the  bottom  of  the  upper  section  is  pierced  by 


262 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


123.  In  some  sections  of  our  country  "bad  water"  is  the  bane  of  the  pho- 
tographer, and  he  must  distil  all  the  pure  water  required  in  his  work.  In 
some  establishments  the  still  is  running  nearly  all  the  time.  The  con- 
struction of  a  still  is  not  difficult  or  expensive  when  the  proper  principles  are 
followed. 

The  matter  of  supplying  it  with  heat  must  also  be  considered.  I  have 
found  an  alcohol  lamp — or  rather  one  of  the  tiny,  patent  alcohol  stoves  sold 
everywhere,  to  do  an  immense  amount  of  work,  and  it  is  al  ivays  clean. 

After  distilled  water  is  procured  a  convenient  receptacle  for  supplying  it  is 
a  comfort.  Again  we  refer  to  the  notes  for  help. 

numerous  holes,  through  which  the  water  from  the  melted  ice  reaches  the  lower  pail.  I 
place  in  the  upper  pail  from  five  to  eight  pounds  of  ice  each  morning,  and  place  it  in  the 
upper  section  of  the  box.  This  will  be  sufficient  to  keep  the  two  chambers  at  a  tem- 
perature of  about  sixty  degrees  for  twenty-four  hours.  The  upper  section  contains  the 
collodion  and  a  small  11  x  14  bath;  the  lower  section  contains  the  large  17  x  20  bath,  and 
the  stock  of  alcohol  and  ether,  and  such  other  things  as  I  wish  to  keep  cool.  In  the 
drawing,  A  A  is  the  box;  B  B,  baths;  C  C,  upper  and  lower  chambers;  D,  pail  in  two 
sections;  E,  ice;  F,  perforated  bottom  of  upper  chamber;  G,  door  to  upper  section, 
which,  for  convenience,  I  have  hinged  at  the  bottom,  and  drops  forward  in  opening ;  ff, 
door  to  lower  section. 

I  have  used  this  chamber  for  about  eight  years,  with  uniform  success.  If  heat  is 
required  in  winter,  a  gas-jet  may  be  burned  in  lower  section. — J.  H.  SCOTFORD. 

123.  I  give  you  a  sketch  of  an  apparatus  for  distilling  pure  water.  Some  sixteen 
months  ago  a  man  told  me  about  it,  and  I  went  right  over  to  the  tinman's,  chalked  out 
a  drawing  on  his  wall,  and  an  hour  afterward  I  had  the  whole 
aifair  "biting"  and  at  a  cost  of  only  one  dollar;  here  it  is.  It 
can  be  made  of  tin  plate,  or,  better,  tinned  copper.  It  is  so 
perfectly  simple  that  really  it  requires  no  explanation.  A  is  a 
round  vessel,  and  the  same  height  as  its  diameter,  with  a  stout 
wire  around  the  top  edge ;  this  vessel  to  contain  the  water  to  be 
distilled. — J.  EDWARDS  SMITH. 

We  all  know  the  value  of  distilled  water.  The  following 
will  be  found  a  good  plan  for  getting  it,  as  illustrated  by  Fig. 
255. 

A  is  an  ordinary  stone  ice-cooler,  sitting  on  the  shelf  F  in 
any  convenient  place  in  the  dark-room  or  elsewhere;  overhead^ 
for  instance,  out  of  the  way.  The  outlet  B  is  stopped  up  with 
a  cork,  with  a  piece  of  bent  glass  or  metal  tube  through  the 
centre.  Over  this  tube  one  end  of  a  piece  of  one-quarter  inch 
rubber-hose  C  of  the  desired  length  is  stretched,  to  carry  the 

water  wherever  desired.  The  water  is  guided  by  holding  the  hose  in  the  hand,  and 
stopped  by  a  pinch  of  the  thumb  and  finger.  When  not  in  use,  the  lower  end  of  the 


FIG.  254. 


DARK-ROOM    CONTRIVANCES, 


263 


FIG.  255. 


124.  Careful  filtration  is  a  necessity  with  many  of  the  solutions  used  in  pho- 
tography, with  varnish,  emulsions  and  so  on.  The  lighter  ones  are  managed 
with  paper  filters.  Others  must  be  treated  with  apparatus  contrived  for  the 
purpose.  The  contrivances  are  quite  as  numerous  as  their  uses.  Sometimes 
the  apparatus  used  for  filtering  does  not  filter — at  least  not  effectually.  There 
should  be  no  economy  practiced  in  this  direction.  Get  the  best  and  save 
the  most. 

hose  is  stretched  over  the  piece  of  glass-tube  D,  which  has  been  heated,  drawn  to  a 
point,  and  inserted  in  the  second  cork  E,  which  is  fastened  under  the  shelf  F,  or  at  any 
other  convenient  place.  Bore  a  hole  in  the  shelf  for  the  cork 
E  to  fit  in. 

It  will  be  seen  that  when  about  to  use  the  water,  the  hose 
should  be  pinched  tight,  withdrawn  from  the  point  D,  and  the 
end  guided  to  the  spot  where  the  water  is  needed.  The  same 
arrangement  may  be  used  for  other  purposes  also.  To  make 
the  cork  staunch  in  any  such  vessel,  first  fit  it  quite  tight,  and 
then  dip  it  in  hot  paramne ;  then  heat  the  opening  for  the  cork, 
and  press  it  in,  and  when  cool,  it  will  be  water-tight. — J.  W. 
OSBORNE. 

124.  To  make  a  plaited  filter,  take  a  rectangular  piece  of  paper 
and  fold  it  like  a  sheet  of  paper — that  is,  to  bring  two  corners 
together,  then  (Fig.  256)  fold  10  upon  2,  and  now  always  open 
the  last  fold  after  folding;  then  10  upon  6,  then  1 — 10  upon  1 — 
8,  then  2  upon  8,  then  2  upon  6,  2  upon  4,  and  10  upon  4. 
This  will  produce  seven  folds,  all  on  one  side  of  the  paper. 
Make,  now,  folds  between  each  of  these,  so  as  to  raise  ribs  on 
the  opposite  side  of  the  paper.  Cut  off  the  projecting  corners, 
to  give  the  whole  a  circular  shape ;  open  it,  and  form  it  into  a 
cup  (Fig.  257). — ALEXANDER  SPICER. 


FIG.  257. 


I  take  a  common  glass  chimney,  such  as  is  used  for  coal-oil  lamps,  invert  it  in  the  top 
of  a  cyanide  or  other  wide-mouthed  bottle,  cork  up  both  ends  of  the  chimney,  cut  a  hole 


264 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  258. 


When  paper  filterers  are  used  see  that  they  are  clean  and  free  from  dust. 
They  may  be  used  over  and  over  again  for  some  purposes  provided  they  are 
clean. 

through  the  lower  cork,  and  run  a  glass  tube  through  it  from  the  bottle  to  the  chimney ; 
now  cut  a  few  slits  in  the  same  cork,  and  then  wind  clean  cotton-wool  around  it,  and  it 
is  ready  for  use.  The  tube  remains  a  fixture  in  the  cork,  but  can 
be  removed  to  clean,  etc.  Pour  the  ^collodion  into  the  inverted 
chimney,  and  cork  up  the  upper  end,  then  you  have  as  nice  a  filter 
as  you  can  desire  (Fig.  258). 

Perhaps  you  do  not  quite  understand  what  I  mean,  so  I  will 
make  a  rough  sketch,  which  will  make  it  plainer  to  you. — C.  AL- 
FRED GARRETT. 

As  it  is  usually  a  matter  of  some  importance  in  filtering  a  liquid 
that  the  filter  should  be  kept  full,  and  as  it  is  very  tedious  to  be 
continually  attending  and  feeding  during  the  operation,  the  follow- 
ing simple  device  will,  I  hope,  be  found  of  great  service : 

The  bottle  containing  the  liquid  to  be  filtered  is  placed  on  a  shelf 
or  stand  above  the  level  of  the  filter.  Through  the  cork  (which 
must  fit  air-tight;  it  is  better  to  put  varnish  around  the  top)  pass 
two  bent  tubes ;  one  end  of  b  dips  far  enough  down  into  the  liquid 
to  draw  off  just  the  amount  you  wish,  the  other  descending  deep 
into  the  filter.  The  tube  a,  at  one  end,  reaches  just  below  the 
mouth  of  the  bottle,  the  other  end  being  fixed  at  the  height  in  the 
filter  at  which  you  wish  to  keep  the  solution. 

Start  the  apparatus  by  sucking  the  liquid  into  the  tube,  b ;  it 

will  flow  steadily  until  it  reaches  and  closes  the  lower  end  of  the  tube  a,  when  by  cut- 
ting off  the  ingress  of  air  into  the  bottle,  it  stops  any  further  flow  till  the  liquid  in  the 
filter  again  sinks  below  the  end  of  a.  The  minute  a  is  clear,  the  flow  will  again  com- 
mence, to  be  stopped  as  before,  when  a  is  covered.  When 
the  liquid  in  the  bottle  sinks  below  the  end  of  b,  the  whole 
operation  ceases  (Fig.  259). 

Determine  beforehand  how  much  of  your  solution  you  wish 
to  filter,  set  b  accordingly,  start  the  thing  working,  and  then 
leave  it  to  itself,  until  you  have  need  of  the  filtrate. — REV. 
CLARENCE  A.  WOODMAN. 

I  send  you  a  cut  of  my  Universal  Filter  (Figs.  260  and  261). 
I  use  it  as  follows : 

For  varnish  or  albumen  I  use  an  ordinary  tin  funnel ;  I 
first  solder  a  tin  band  one  inch  wide  on  the  top,  then  make 
the  adjustable  top  of  tin  to  fit  in  loosely  ;  this  consists  of 
another  band  two  inches  deep.  Spread  a  piece  of  cotton 
flannel  over  the  narrow  band  on  the  top  of  the  funnel,  with 


FIG.  259. 


DARK-ROOM    CONTRIVANCES. 


265 


I  have  given  so  many  hints  from  wise  heads  and  wonderful  dark-rooms  that 
I  am  sure  no  one  need  use  dirty  solutions. 

nap  side  up,  then  crowd  in  the  wide  band,  which  will  draw  the  flannel  snug.  The  filter 
is  then  ready.  For  varnish,  wet  the  flannel  with  alcohol;  for  albumen,  use  a  piece  of 
muslin  if  the  flannel  does  not  filter  fast  enough. 


PIG.  260. 


FIG.  261. 


FIG.  262. 


I  have  used  it  for  collodion,  varnish,  cream,  milk,  fat,  paint,  albumen,  honey,  and  a 
host  of  other  things  I  will  not  mention. — S.  L.  PLATT. 

I  append  drawings  of  my  filtering  apparatus,  with  full  directions  for  its  construction. 
Let  A  (Fig.  262)  represent  a  piece  of  wood  one  inch  thick,  and  a  half  disk  sawed  out,  half 
the  circumference  of  the  demijohn,  B.  There  is  also  a  piece  of  soft  wire,  D,  fastened  at 
one  end  of  the  piece  of  wood,  A  ;  at  the  other  end  it  is  bent  so  as  to  hook  into  the  screw 
eye,  E,  and  thus  keeps  the  inverted  demijohn,  B,  in  its  place.  This  piece  of  wood  is 
fastened  at  the  proper  height  to  any  convenient  wall  of  the  apartment.  The  demijohn, 
E,  capable  of  containing  the  entire  solution  of  the  bath,  is  provided  with  a  cork,  through 
which  passes  a  glass  tube  about  three  or  four  inches  long  and  a  quarter  of  an  inch  in 
diameter;  a  portion  of  the  cork  is  also  cut  out,  as  is  represented  in  the  drawing,  fl 
Around  the  neck  of  the  demijohn  are  two  pieces  of  wood  joined  together,  which  enclose 
the  neck,  (7.  The  demijohn  being  charged  with  the  solution  and  corked,  is  inverted 
over  a  funnel  containing  the  filter.  The  uprights,  H  H,  support  the  piece  G,  and  keep 
it  from  resting  on  the  funnel.  This  funnel  rests  in  a  hole  cut  out  of  the  shelf,  7,  which 
latter  is  supported  by  the  brackets  JJ,  which  are,  like  the  pieced,  fastened  to  the 


266 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  263 


125.  The  subject  of  development  is  treated  elsewhere,  so  that  this  depart- 
ment may  be  devoted  entirely  to  the  contrivances  which  make  the  dark-room 

wall.  The  lip  of  the  funnel  either  dips  into  another  similar  demijohn,  or,  if  you  prefer, 
into  the  bath-holder.  You  will  observe  that  the  instant  the  demijohn,  A,  is  inverted, 
the  solution  commences  running  out,  and  the  air-bubbles  in,  and  the  solution  would 
eventually  all  run  out,  were  it  not  for  the  fact  that  the  mouth  of  the  demijohn  dips  below 
the  top  of  the  funnel;  consequently,  as  soon  as  the  solution  reaches  the  cork  in  the  demi- 
john, the  atmosphere  is  cut  off  from  entering  the  hole  in  the  cork,  and  thus  matters 
come  to  a  standstill  until  sufficient  solution  has  run  through  the  filter  to  again  allow  the 
air  to  enter  the  demijohn,  when  the  solution  runs  out  as  before,  etc.  Should  your  bath 
consist  of  three  or  four  gallons  of  solution,  which  would  require  many  hours  to  filter, 
you  have  merely  to  start  this  simple  piece  of  work  at  night  when  you  go  home,  and  in 
the  morning  the  work  is  done. — W.  KURTZ. 

125.  To  protect  pyro  solution,  use  a  layer  of  oil  (I  use  good  "  headlight")  about  an  inch 
thick.     Same  for  ferrous  sulphate  or  ferrous  oxalate  solution.     The  potassic  oxalate  solu- 
tion has  a  disagreeable  habit  of  crawling  up  the 
inside  of  the  bottle  and  around  the  neck.     A  thin 
layer  of  oil  is  sufficient  to  prevent  this. 

The  method  of  operating  is  plain.  Simply  blow 
into  the  tube  A  (Fig.  263),  and  the  pressure  on  the 
liquid  will  force  it  out  of  tube  B  as  desired.  Don't 
tip  up  the  bottle  towards  the  lower  end  of  B,  or  it 
will  be  apt  to  act  as  a  siphon.  For  the  same  reason 
the  bent  portion  of  B  should  not  have  the  end 
lower  than  the  level  of  the  liquid  in  the  bottle. 
If  this  bottle,  in  its  simple  form  is  not  elaborate 
enough  to  suit,  just  attach  a  piece  of  rubber  tubing 
to  A  with  a  rubber  bulb  (such  as  are  fitted  to  the 
ordinary  atomizers)  at  the  end,  and  squeeze  this 
in  the  hand.  This  will  enable  you  to  allow  the 
bottle  to  stand  on  a  shelf,  which  may  be  a  gain 
when  using  large  bottles. — H.  SCHOONMAKER. 

Various  forms  of  holder  have  been  proposed,  for 
supporting  the  plate  during  its  development  and 
redevelopment,  where  this  last  is  required,  in  order 
to  save  the  hands  from  the  silver  stains,  which  are 
apt  to  be  caused. 

About  a  year  ago,  an  idea  occurred  to  me,  which 
Mr.  Zentmayer  carried  into  execution  for  me,  and 
which  has  proved,  after  very  thorough  trial,  to  be 

free  from  all  objection.  Fig.  264  will  give  a  clear  idea  of  it.  A  brass  rod,  just  stout 
enough  to  have  the  necessary  stiffness  without  being  heavy,  is  inserted  into  a  wooden 
handle,  also  another  similar  piece,  much  shorter.  Each  of  these  carries  an  arm  about 
three  inches  long,  the  upper  part  of  brass,  but  the  lower  half  of  solid  silver.  At  the 


B 


DARK-ROOM    CONTRIVANCES. 


267 


convenient  and  comfortable,  and  which  serve  to  make  the  manipulator's  lot  a 
happy  one.  For  those  who  wish  not  to  soil  their  fingers,  the  caterers  to  the 

bottom  this  silver  piece  is  bent  short  at  right  angles.  The  two  arms  are  connected 
by  a  rod  passing  through  both.  In  one,  it  simply  turns  round,  in  the  other  hole  there  is 
a  screw-thread  cut,  with  a  corresponding  thread  on  the  rod.  This  last  has  at  its  right- 
hand  end,  a  mill-head.  It  is  evident  that,  by  turning  this  mill-head,  the  arms  are  made 
to  approach  or  separate. 

FIG.  264. 


m 


FIG.  265 


The  space  between  the  arms  is  such  as  to  correspond  with  the  size  of  the  plate  most 
frequently  used.  A  holder  can,  however,  be  used  for  two  sizes  of  plates,  taking  the 
larger  size  by  its  breadth,  and  the  smaller  by  its  length,  as  the  construction  admits  of  a 
certain  degree  of  play.  Thus,  the  writer's  takes  a  6£  by  8£  plate  the  long  way,  and  an 
8  by  10  the  short  way,  there  being  but  half  an  inch  difference. 

A  firmer  grip  of  the  holder  is  obtained  by  partly  squaring  the  round  handle,  which 
•could  not  be  very  clearly  shown  in  the  figure. — M.  CAREY  LEA. 

I  desire  to  describe  a  very  simple  little  piece  of  apparatus,  which  I  have  lately  devised, 
for  holding  the  developing  solution,  and  which  is  in  working  use. 

It  consists  of  a  two-pound  acetic  acid  bottle  A  (Fig.  265),  with  its  bottom  removed,  by 
the  "alcohol  string," or  other  of  the  well-known  methods,  sustained  in  an  inverted 
position,  as  clearly  shown  in  the  sketch,  against  the  wall  of  the  dark  room  over  the 
developing  sink  or  tub,  within  easy  reach.  In  the  usual  place  is  a  good,  tightly-fitted 
cork — sufficiently  so  to  withstand  the  pressure  of  the 
bottle  full  of  developer,  into  a  hole  in  which  a  cork  is 
placed  from  the  outside  a  small  faucet  JB,  and  to  con- 
tinue the  connection  to  the  interior  of  the  bottle,  a 
short  glass  tube  C,  which  should  be  of  such  a  length 
as  to  reach  to  about  where  the  straight  sides  of  the 
bottle  begin.  D  is  a  scale  constructed  as  follows : 
Paste  upon  the  outside  of  the  bottle  in  a  perpendicular 
position,  a  strip  of  white  paper  one  inch  wide.  Open 
the  faucet  B.  Pour  in  water  (through  the  top  of  the 
bottle)  to  fill  up  to  the  top  of  the  tube  C,  where,  of 
course,  all  excess  will  overflow.  Make  a  mark  upon 
the  strip  of  paper  where  the  water  now  stands ;  this  is 
zero.  Close  the  faucet.  Now  measure  in  your  gradu- 
ate sixteen  ounces  of  water,  and  pour  into  the  bottle ; 
mark  the  level  of  the  water  now  upon  the  paper  strip, 
and  then  divide  down  to  zero,  with  dividers,  into  six- 
teen spaces.  These  will  represent  ounces,  and  number  them  accordingly.  This  constructs 
the  scale  and  makes  the  instrument  self-measuring.  Now  empty  out  all  the  water  by 


268 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  266. 


trade  supply  many  little  conveniences  which  I  need  not  describe  to  you. 
Notes,  however,  of  one  or  two  things  which  may  have  been  overlooked,  come 
in  place  right  here. 

removing  the  holder  from  the  bracket.  Replace.  Now  fill  up  to  zero  with  your  common 
admixture  of  developer.  Below  this  now  it  will  never  fall,  and  is  considered  to  be  empty. 
Its  manner  of  use  is  already  anticipated  by  the  reader.  Faucet  closed.  From  your 
stock-bottle  of  concentrated  iron  solution,  pour  two,  three,  or  four  ounces,  as  your  formula 
or  judgment  dictates,  which  amount,  remember,  is  being  indicated  upon  your  paper  scale 
as  you  pour ;  then  the  water,  acetic  acid,  alcohol,  all  of  which  is  being  measured  and 
indicated  in  the  same  manner. — WILLIAM  EGBERT  BROOKS. 

For  a  long  time  I  have  been  using  a  very  convenient  device  to  give  a  continuous  rock- 
ing motion  to  the  dishes  containing  the  negative  and  developer  for  dry  plates.  It  con- 
sists simply  of  a  pendulum,  made  from  an  iron  rod,  the  upper  portion  of  which  is  bent 

into  an  elbow,  and  furnished  with  a  small  wooden  or 
copper  wheel.  The  rod  passes  through  the  laboratory- 
table,  in  which  a  hole  has  been  made,  and  there  is  its 
point  of  suspension.  The  lower  extremity  of  the  rod, 
which  reaches  nearly  to  the  floor,  carries  a  weight  of 
about  nine  pounds.  When  an  oscillating  motion  is 
given  to  this  weight,  the  elbow,  which  is  elevated  a 
little  above  the  level  of  the  table,  rises  and  falls  alter- 
nately, transmitting  its  vertical  movement  to  the  bottom 
of  the  dish  resting  on  it.  This  dish  has  no  backward 
or  forward  motion,  as  the  small  wheel  turns  in  follow- 
ing the  oscillatory  motion.  The  weight  having  been 

set  in  motion  will  continue  swinging  about  three  minutes,  slowly  and  regularly  (Fig. 
266). — E.  COURTIER. 

Mons.  Gabert's  novel  developing  apparatus  is,  I  may  say,  an  hydraulic  engine,  and  has 
the  advantage  over  all  other  oscillating  apparatus,  that  it  continually  goes  on  working 
without  any  aid  from  the  photographer. 

In  looking  at  Fig.  267,  it  can  be  seen  that  this  apparatus  resembles  a  large  pair  of 
scales.  D  is  the  beam,  supported  by  two  bearings,  O  G,  firmly  screwed  into  a  strong 
table ;  on  one  end  of  the  beam  is  a  flat  space  to  stand  the  developing  tray,  on  the  other 
end  is  attached  the  hydraulic  box.  When  the  tap 
A,  is  opened,  the  water  from  a  reservoir  fills  up  the 
box  to  the  dotted  line,  C;  this  end  of  the  scale  has 
now  become  the  heavier  and  falls,  and  shoots  out 
all  the  water ;  the  other  end  of  the  beam,  bearing 
the  tray,  now  falls  down,  the  water  continues  to 
fill  up,  and  causes  the  other  end  to  go  down,  and 
so  on  every  minute,  or  part  of  a  minute,  and  so  keeps 

the  liquid  in  the  developing  tray  in  constant  agitation.  The  springs  at  each  end  of  the 
apparatus  are  to  soften  the  shock,  and  by  their  elasticity  aid  the  end  to  rise.  In  order 


Fro.  267. 


DARK-ROOM    CONTRIVANCES. 


269 


The  "  veteran  "  will  smile  at  some  of  these  niceties,  but  that  is  often  because 
he  will  not  employ  them  and  does  not  realize  how  very  useful  and  convenient 
they  are. 

I  never  show  any  disrespect  to  a  manipulator  who  goes  about  with  stained 
fingers  and  varnished  thumbs,  and  yet  in  these  days  when  photography  is 
becoming  more  and  more  one  of  the  refined  arts  it  behooves  us  all  to  present 
it  to  the  public  as  sweetly  as  can  be. 

A  real  careful  worker  may  maintain  a  cleanly  appearance  of  things  without 
any  of  those  "  extra  tools."  I  have  the  highest  respect  for  such  a  worker. 

In  all  these  instances  have  good  "  tools."  You  have  no  right  to  expect 
good  results  unless  you  do. 

to  obtain  the  proper  equilibrium,  a  weight  is  laid  upon  the  beam,  D,  and  shifted  at  will 
toward  or  from  the  fulcrum. — PROF.  STEBBING. 

Some  developing  dodges  come  in  good  right  here.  The  first  is  a  plate  tongs  (plat- 
tenzangen),  a  contrivance  for  handling  the  plate  during  development,  and  other  opera- 


FIG.  268. 


FIG.  269. 


FIG.  270. 


tions  wherein  it  is  desirable  to  keep  the  fingers 
clean,  or  to  preserve  them  from  the  action  of 
the  solutions. 

A  band  of  silver  is  so  bent  as  to  answer  the 
purpose,  strong  enough  to  secure  the  safety  of 
the  plate  during  the  handling  (Figs.  268,  269). 

The  other  is  a  contrivance  for  rocking  the 
plate  during  the  development.  Its  construction 
is  made  very  plain  by  the  drawing.  This  ma- 
chine (Schankelapparat)  may  be  large  or  small, 
according  to  your  requirements.  The  dish  con- 
taining the  plate  is  set  upon  the  bed-plate,  fas- 
tened in  place,  the  pendulum  started,  and  the 
operation  goes  on  automatically  (Fig.  270). 

We  are  indebted  to  our  German  friends  for  both  of  these  useful  inventions. — E.  S.  W. 


270 


WILSON'S    QUARTER    CENTURY    IJST    PHOTOGRAPHY. 


As  the  mechanic  is  known  by  the  tools  he  works  with,  so  too  should  the 

artist  photographer  use  none  but  the  best,  and  have  them  conveniently  placed 

and  in  good  order  for  immediate  handling.     Then,  and  only  then,  will  he 

• 
The  following  idea  for  a  developing  cup  may  be  useful  to  those  who  use  the  gelatino- 

developer.     A  (Fig.  271),  opening  to  pour  in  the  developer,  which,  filtering  through  the 

perforated  partition  B,  passes,  when  used,  through  opening 
of  arrow,  O,  out  of  mouth,  D.  F  is  a  covering  to  prevent 
the  unfiltered  solution  from  overflowing  when  tilted  by  the 
operator.  It  might  be  difficult  and  expensive  to  have  them 
made  of  porcelain  or  glass.  Could  they  not  be  made  of 
gutta-percha?  Of  course,  when  the  photographer  has  deter- 
mined to  use  gelatine  in  the  developer,  he  will  have  some 
ready  filtered ;  but  when  some,  after  standing,  is  required 
speedily,  a  vessel  like  the  above  would  surely  prevent  a  plate 
from  being  injured.— DAVID  DUNCAN. 

By  using  the  little  pipettes  described  below  (Fig.  272),  the 
photographer  can  take  from  any  solution  desired,  drop  by 
drop.  They  are  five  or  six  inches  in  length,  and  about  three- 
eighths  of  an  inch  in  diameter.  The  photographer  can 
make  them  for  himself,  by  procuring  a  glass  tube  ten  or 

twelve  inches  long  and  of  the  proper  size.    Heat  it  in  the  middle  by  gradually  lowering  it 

into  the  flame  of  a  spirit-lamp,  keeping'it  constantly  turning  so  as  not  to  expand  the  glass 

unevenly,  thereby  causing  it  to  break.    When  it  has  become 

very  soft  and  pliable,  it  must  be  pulled  suddenly  apart,  thus 

causing,  the  separated  parts  to  be  drawn  out  into  very  fine 

points ;  break  off  one  of  these  points,  and  you  will  have  a  tube 

with  a  very  fine  aperture.     Procure  a  piece  of  elastic  rubber 

tube  two  or  three  inches  long,  having  an  inside  diameter  a  little 

smaller  than  the  outside  diameter  of  the  glass  tube;  close  one 

end  with  a  cork,  and  slip  the  other  end  on  to  the  glass  tube,  and 

your  instrument  is  complete.     If  you  want  a  larger  hole  in  the 

end,  you  have  only  to  break  off  more  of  the  point. — D.  EDSON 

SMITH. 

I  have  found  a  great  convenience  in  the  employment  of  a  new 

dropping-bottle,  the  description  of  which,  I  think,  will  be  of 

service  to  our  readers.     It  is  easily  constructed,  and  works  very 

well,  little  or  no  evaporation  taking  place.     To  fit  up  the  appa- 
ratus, fit  cork  b  (Fig.  273)  firmly  into  the  neck  of  bottle  a;  now 

pull  over  the  neck  the  lower  part  of  the  India-rubber  pear,  and 

fasten  it  on  with  a  string,  or  with  iron  or  brass  wire.     Now  fit 

cork  c  into  the  top  of  the  India-rubber  pear,  and  fasten  it  tightly  in  the  same  manner. 

Take  the  curved  glass  tube,  and  push  it  down  the  centre  holes  of  the  two  corks  into  the 

bottle ;  the  apparatus  will  appear  as  in  Fig.  274. 


FIG.  272. 


DARK-ROOM    CONTRIVANCES. 


271 


reap  the  benefit  of  seeing  how  easy  it  is  to  accomplish  the  mysteries  of  the 
dark-room. 

To  set  it  at  work,  press  the  India-rubber  pear  in,  taking  care  that  the  thumb  covers 
the  small  hole  e;  the  air  contained  in  the  pear  will  rush  through  the  small  hole  in  cork 
b,  and  press  upon  the  liquid  in  the  bottle.  The  liquid  will  make  its  way  up  the  glass 
tube,  and  make  its  exit  either  rapidly  or  in  drops,  according  to  the  pressure  of  the  hand 
upon  the  India-rubber  pear. 

FIG.  273  FIG.  274. 


FIG.  275. 


a,  glass  bottle  with  tubular  neck.     6,  cork  perforated  by  two  holes,     c,  cork  perforated  by  one  hole,    d,  India- 
rubber  hollow  pear,     e,  small  hole  punched  in  India-rubber  pear.    /,  a  curved  glass  tube. 

To  fill  the  apparatus,  draw  out  the  glass  tube,  and  put  down  a  long,  thin  tube,  with  a 
glass  funnel  at  the  end.  The  liquid  will  easily  make  its  way  down,  as  the  air  will  be 
expelled  by  the  hole  in  the  cork  into  the  India-rubber 
pear,  and  thence  through  the  thumb-hole  e  into  the 
atmosphere. — PROF.  E.  STEBBING. 

I  find  the  four  poster  a  very  useful  piece  of  appa- 
ratus for  drying  plates.  I  will  give  the  size  of  mine; 
but,  of  course,  other  sizes  may  be  more  convenient 
(Fig.  275).  The  four  posts  are  six  feet  long  and  one 
inch  and  a  half  square.  The  first  operation  is  to 
place  these  posts  in  pairs,  and  mark  upon  them  lines 
indicating  the  places  where  the  supports  for  the 
shelves  are  to  be  screwed.  The  intervals  between 
these  supports  must  be  according  to  the  size  of  the 
plates  which  are  to  stand  upon  the  finished  structure. 
My  shelves  are  placed  at  different  distances,  so  as  to 
accommodate  different  sized  plates.  The  supports, 
two  feet  long,  and  made  of  stuff  one  inch  by  three- 
quarters  of  an  inch  thick,  are  now  screwed  into  their 
places,  when  the  pair  of  posts  have  the  appearance 
of  two  ladders.  The  shelves  must  now  be  taken  in 
hand,  and  are  conveniently  made  before  being  put 
into  position.  They  are  made  of  laths,  about  one 


272       WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


126.  The  siphon  is  an  article  which  should  hang  as  conveniently  as  the  fire- 
,  extinguisher,  for  in  case  your  tanks  become  clogged  and  threaten  an  overflow, 

inch  by.  three-eighths  of  an  inch,  which  can  be  bought  by  the  dozen  at  any  saw-mill. 
These  can  be  carefully  measured  off  with  pencil-marks,  the  upper  laths  being  spaced  out 
according  to  the  size  of  the  plates  which  are  to  stand  upon  them,  the  lower  ones  being 
intended  for  the  top  edge  of  the  leaning  plates  to  rest  upon.  At  each  point  of  crossing, 
the  junction  must  be  made  good  by  one  French  wire  nail. 

When  the  shelves  are  all  in  position,  the  general  structure  can  be  screwed  together 
with  tie-pieces,  the  back  and  sides  filled  in  with  black  glazed  calico,  and  a  blind  of  the 
same  material  fitted  to  a  roller  in  front.  In  my  four-poster  a  closed  gas-stove  is  fitted 
to  the  lower  part ;  but  this  is  not  necessary  for  gelatine  plates,  which  will  soon  dry  if 
the  room  itself  be  not  damp.  The  skeleton  arrangement  of  the  shelves  permits  a  con- 
stant current  of  air  to  circulate  round  about  the  plates;  but  a  better  current  can  be  in- 
sured by  taking  advantage  of  the  rising  property  of  warm  air  in  the  following  manner. 

It  is  well  known  that  the  admixture  of  certain  salts  with  ordinary  water  raises  the 
boiling-point  of  the  liquid  far  above  the  stereotyped  212  degrees.  Acetate  of  soda 
stands,  I  believe,  at  the  head  of  the  list  in  raising  the  boiling-point  to  256  degrees. 

My  suggestion  is,  that  at  the  bottom  of  the  drying-box  (which  should  be  pierced  with 
holes  for  the  admission  of  air)  should  stand,  on  four  short  feet,  a  metallic  vessel  filled 
with  a  boiling  solution  of  the  soda.  This  hot  box  would  cause  a  constant  draught  of 
warm  air  to  rise  to  the  plates  standing  in  racks  above  it,  and  the  retained  heat  would 
dry  the  thickest  film  in  a  few  hours. 

The  four-poster  is  highly  useful  for  other  purposes  than  the  mere  drying  of  newly 
made  plates.  It  can  be  used  as  a  rack  for  glasses  when  they  have  received  their  final 
rinse  under  the  tap  after  washing.  It  will  serve  the  same  purpose  for  negatives,  which 
will  quickly  dry  in  such  a  position,  particularly  if  the  erection  be  brought  close  to  a  fire. 
At  other  times  it  will  form  a  nest  of  useful  shelves,  where  cardboard,  paper,  glass,  and 
other  things  can  be  conveniently  stored.  It  may  be  modified  in  various  ways  to  suit 
individual  wants.  Thus  it  may  be  convenient  to  shorten  the  legs,  so  that  the  thing  can 
stand  on  a  vacant  table;  or  the  same  kind  of  shelves  can  be  fitted  to  an  existing  cup- 
board, in  which  case  efficient  light-tight  ventilation  must 
be  strictly  enforced. — T.  C.  HEPWORTH. 

126.  My  siphon  is  supplied  with  a  glass  tube  at  one  or 
both  ends,  so  as  to  fit  tightly  through  the  disk  a  (Fig.  276). 
The  disk  is  covered  on  the  under  side  with  rubber,  so  that 
.  by  pressure  it  will  make  an  air-tight  connection  with  the 
mouths  of  bottles  or  other  vessels,  which  you  may  wish 
to  empty  or  fill.     Now,  as  in  the  illustration,  to  empty 
— -71  the  bath  B  into  the  bottle  C,  lower  the  bottle  and  press 
f     firmly  on  the  padded  disk  (a),  and  with  the  mouth  draw 
air  from  C  through  D.     Or,  if  you  wish  to  empty  C  into 

B,  raise  C,  press  on  the  disk  as  before,  and  blow  through  Z>,  which  will  force  the  liquid 
out  of  C  to  B.  In  this  way  you  can  empty  or  fill  any  vessel  that  the  disk  (a)  will  cover, 


FIG.  276. 


DARK-ROOM    CONTRIVANCES.  273 

it  might  save  you  as  much  damage  as  the  other.  Again,  for  emptying  solu- 
tions of  all  kinds  from  one  vessel  into  another  quickly,  the  siphon  is  of  great 
service. 

without  (as  in  the  old  way)  getting  any  of  the  solution  in  your  mouth. — J.  EZKA 
GAUSE. 

Buy  of  any  druggist  a  rubber  bulb  with  an  opening  at  each  end,  about  four  feet  of 
rubber  tubing  and  a  glass  tube  such  as  is  used  in  babies'  nursing-bottles.  Have  the  hole 
in  the  bulb  and  tubing  as  near  the  same  size  as  possible,  and  the  glass  should  be  large 
enough  to  fit  into  the  rubber  snugly,  to  prevent  any  air  from  getting  in.  Use  two  pieces 
of  the  glass,  each  about  one  and  a  half  inches  in  length,  and  press  each  piece  about  half 

FIG.  277.  FIG.  278. 


of  its  length  into  each  end  of  the  bulb ;  cut  the  rubber  tubing  in  two  at  the  centre,  and 
press  the  end  of  each  piece  on  the  glass  tubing,  and  the  siphon  is  complete.  It  requires 
no  cement  to  hold  it  together,  and  when  one  part  becomes  worn  or  injured  a  new  one 
can  be  substituted  without  buying  all  new.  These  different  parts  will  cost  but  from 
seventy-five  cents  to  one  dollar,  and  this  siphon  is  worth  more  than  one  from  a  dealer 
which  costs  two  or  three  times  that  amount,  because  there  are  no  cemented  parts  to  give 
out.  When  not  in  use  it  can  be  rolled  up,  put  in  a  small  box,  and  it  is  out  of  the  way. 
It  is  used  the  same  as  any  bulb  siphon,  by  holding  tightly  the  lower  end  of  it  while 
forcing  the  air  out  of  the  end  in  the  solution  to  be  drawn  by  pressing  together  the  bulb 
(Figs.  277,  278).— W.  D.  CHANDLER. 

Having  used  the  following  method  of  emptying  large  flat  dishes  containing  silver  solu- 
tions for  some  years  past  with  perfect  success,  I  thought  a  description  of  my  method 
might  not  be  unacceptable. 

Every  photographer  knows  how  difficult  it  is  to  pour  back  the  solution  of  nitrate  of 
silver  from  a  large  flat  dish  into  the  stock-bottle  again  without  spilling  some  portion  of 
the  liquid.  By  adopting  the  following  method  not  a  drop  of  solution  need  be  wasted. 
Provide  a  cork  that  will  fit  into  the  neck  of  the  stock-bottle,  and  with  a  cork-borer  bore 
two  holes  in  the  cork,  and  fit  each  hole  with  a  piece  of  glass  tubing,  a  short  piece  and  a 
long  piece.  To  the  short  piece  attach  a  piece  of  India-rubber  tubing  above  the  cork 
and  to  the  other  end  of  the  India-rubber  tubing  attach  another  short  piece  of  glass  tubing. 
The  long  piece  of  glass  tubing  that  passes  through  the  cork  must  project  above  the  cork 
some  little  distance,  and  should  bend  over  slightly,  so  as  to  be  able  to  apply  the  mouth 
easily  to  the  end  of  it.  Place  the  stock -bottle  on  a  chair  or  box  just  below  the  bench  on 
which  the  dish  containing  the  solution  stands ;  insert  the  cork  provided  with  the  two  pieces 
of  tubing  into  the  mouth  of  the  stock-bottle,  and  bring  the  piece  of  India-rubber  tubing 
over  the  side  of  the  flat  dish,  placing  the  piece  of  glass  tubing  at  the  end  of  it  in  the 

18 


274 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGK APHY . 


I  have  added  notes  concerning  a  number  of  methods  of  using  the  siphon 
though  in  principle  they  are  the  same.  A  siphon  needs  to  be  pounded  gently. 
If  forced  violently  and  it  is  caused  to  spurt,  it  will  often  do  more  damage  than 

liquid  to  be  emptied.  Then  apply  the  mouth  to  the  long  piece  of  glass  tubing,  and 
exhaust  the  air  from  the  stock-bottle,  when  the  siphon  formed  by  the  India-rubber  tube 
will  at  once  begin  to  act,  and  continue  running  until  nearly  all  the  liquid  has  passed 
over  into  the  stock-bottle.  The  dish  should  be  tilted  at  one  end.  The  small  remaining 
quantity  of  solution  may  be  easily  poured  out  into  the  bottle. — THOMAS  LATCHMORE. 

How  to  Empty  a  Silver  Bath. — Fig.  270  shows  the  position  when  the  solution  is  passing 
from  the  bath-dish  into  the  bottle.  Fig.  280  shows  the  position  when  the  solution  is 
passing  from  the  bottle  into  the  bath-dish. 

To  make  one  of  these  siphons,  there  is  to  be  obtained  a  bottle  large  enough  to  hold  all 


FIG.  279. 


FIG.  280. 


or  the  greater  portion  of  the  solution,  and  fit  a  cork  air-tight  in  the  neck  of  it.  Now 
procure  as  much  rubber-tubing  as  you  may  wish  (size  to  suit  taste)  cut  a  short  piece  off, 
and  pass  it  just  through  the  cork.  The  long  piece  also  passes  through  the  cork  down  to 
very  near  the  bottom  of  the  bottle.  These  tubes  should  fit  tight,  to  allow  no  air  to  escape 
in  that  direction.  When  all  is  ready  set  the  bottle  in  position  near  the  bath-dish,  but 
lower,  to  allow  the  air  to  act  upon  the  solution  as  it  passes  through  the  tube,  for  herein 
lies  the  secret  of  the  siphon.  Now  place  the  loose  end  of  the  long  tube  into  and  extend- 
ing to  or  near  the  bottom  of  the  dish.  Now  take  the  loose  end  of  the  short  tube  in  the 
mouth  and  draw  upon  it.  When  the  solution  begins  to  run  into  the  bottle,  your  help,  by 
way  of  "  a  sucker,"  is  no  longer  needed,  for  it  will  "  go  alone  "  until  all  of  the  solution  is 


DARK-KOOM    CONTRIVANCES. 


275 


you  can  cleanse  out  of  sight  for  a  long  time, 
all  your  manipulations. 


Give  it  thought,  as  you  should 


FIG.  281. 


out  of  the  dish  and  into  the  bottle.  If  you  wish  to  reverse  this  operation,  set  the  bottle 
higher  than  the  bath-dish,  and  blow  into  the  short  tube  to  start  the  solution. — I.E.  WEBSTER. 
The  accompanying  drawing  (Fig.  281)  represents  a  siphon  for  remov- 
ing silver  solutions  from  trays,  bottles,  etc.,  without  staining  the  fingers, 
spoiling  or  causing  loss  of  solution. 

In  order  to  make  the  above  siphon,  procure  glass  tubing  of  a  7-16 
bore,  bend  the  end  to  a  curve  by  means  of  a  flame ;  at  the  lower  part  of 
/^>v  the  tube  solder  a  3-16  tube,  and  curve  it  upwards  as  in  diagram.     It  is 

1 1   '  only  now  necessary  to  join  to  the  top  of  B  an  India-rubber  bottle. 

Another  tube  is  joined  to  siphon  A  of  sufficient  length  to  permit  it  to 
touch  the  floor  of  the  laboratory.  A  joint  is  made  at  D  with  gutta-percha, 
not  India-rubber.  To  work  the  siphon,  plunge  the  long  end  into  the 
stock-bottle,  which  is  placed  on  the  ground,  in  which  there  has  been 
purposely  left  a  small  quantity  of  the  solution,  put  the  short  end  of  the 
siphon  into  the  tray ;  it  suffices  simply  to  squeeze  the  bottle  in  order  to 
expel  the  air.  Open  the  hand,  and  immediately  the  siphon  is  at  work. 
The  small  quantity  of  liquid  left  in  the  bottle  performs  the  same  office 
as  if  the  end  of  the  tube  had  been  stopped  with  the  finger.  Should  it  be 
necessary  to  decant  the  solution  from  a  deep  bottle,  join  a  piece  of  glass 
tubing  upon  the  short  stem  by  means  of  gutta-percha  tubing. — PROF.  E. 
STEBBING. 

I  am  called  upon  to  give  a  description  of  an  easy  method  of  decant- 
ing collodion,  albumen,  or,  in  fact,  any  other  glutinous  liquids.  I  offer 
for  your  appreciation  a  simple  means  which  I  have  employed  with  suc- 
cess for  the  decantation  of  syrupy  liquids. 

Take  a  tubular  bottle  large  enough  to  contain  collodion  sufficient  for  a  day's  work ; 
into  the  lower  hole  put  a  cork,  through  which  has  been  passed  a  small  bent  glass  tube, 
which  latter  should  be  a  little  longer  than 
the  bottle  is  high  "(Figs.  282  and  283).  The 
bottle  being  now  filled  with  collodion  is  al- 
lowed to  stand  all  night,  so  that  all  dirt  and 
undissolved  cotton  may  fall  to  the  bottom, 
a  cork  being  placed  in  the  neck  of  the  bottle, 
and  one  in  the  top  of  the  glass  tube,  to  pre 
vent  evaporation.  (Vulcanized  India-rub- 
ber corks,  tubes,  etc.,  should  not  be  used  for 
collodion,  for  the  sulphur  which  is  in  them 
will  be  dissolved,  and  the  silver  bath  will 
become  contaminated.)  The  next  morning 

the  collodion,  being  fit  for  work,  is  extracted  from  the  bottle  by  lowering  the  glass  tube 
(Fig.  284),  previously  removing  the  corks  from  the  bottle  and  tube.     Air-bubbles  may 


FIG.  282.        FIG.  283.        FIG.  284. 


276         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

127.  The  emulsion  processes  have  almost  driven  the  wet  collodion  process 
out  of  use,  and   yet,  for  the  sake  of  those  who  practise   it,  and   for  "  auld 
lang  syne  "  a  few  remembrances  of  it  are  here  recorded. 

The  dipper  and  the  nitrate  bath  are  to  be  had  of  all  the  dealers.  A  dipper 
of  silver  wire  is  cleanest  and  best,  but  it  may  be  of  wood  or  rubber. 

Litmus  paper  is  about  the  humblest  member  of  the  dark-room  contrivances, 
but  its  office  is  an  important  one,  and  it  should  always  be  conveniently  placed. 

128.  After  the  careful  and  neat  photograpner  has  occupied  a  carefully  con- 
be  prevented  by  receiving  the  collodion  on  the  side  of  the  neck  of  the  collodionizing 
bottle.     The  excess  of  collodion  poured  on  to  the  plate  should  be  received  into  another 
bottle  and  set  apart  until  the  evening,  when,  after  adding  ether  and  alcohol,  of  which  it 
has  been  deprived  by  evaporation,  and  some  new  collodion  to  replace  that  used  during 
the  day,  it  is  added  to  what  remains  in  the  decauting-bottle,  and  is  fit  for  use  again  the 
next  morning.    This  system  has  the  advantage  of  suppressing  the  glass-tap,  which  often 
sticks  in  a  disagreeable  manner,  or,  what  is  perhaps  worse,  leaks. — LEON  VIDAL. 

127.  When  physicians  and  pharmaceutists  buy  litmus-paper,  "they  generally  make 
the  same  mistake  that  the  photographer  does,  and  demand  that  it  shall  be  deep  in  color, 
that  the  blue  shall  be  very  blue  and  the  red  very  red.     This  is  wrong  in  principle  and 
practice,  particularly  when  slight  traces  of  alkalinity  or  acidity  are  often  important,  and 
the  palest  instead  of  the  deepest  paper  should  always  be  selected.     What  is  sold  as  '  a 
sheet  of  litmus-paper'  should  never  be  less  than  four  inches  by  twelve,  or  three  by 
eighteen.     Such  a  sheet  cut  lengthwise  through  the  middle  gives  a  strip  which,  when 
cut  crosswise  into  strips  a  quarter  or  three-eighths  of  an  inch  wide,  is  of  a  convenient 
size  and  form  for  use.    The  sheets,  one  paler  and  one  deeper  of  the  same  color,  if  desired, 
should  be  rolled  up  together  in  a  tight  roll,  slipped  into  a  test  tube  and  corked.     In 
corked  test-tubes  they  keep  unchanged  for  an  indefinite  time,  while  the  test-tubes  when 
empty  and  corks  are  always  worth  their  cost  to  those  who  use  litmus-paper.     In  this 
form  of  sheets,  however,  the  paper  is  not  so  convenient  for  the  experimentalist  as  when 
<?ut  into  strips  one  to  two  inches  long  and  a  quarter  of  an  inch  wide ;  apd  the  writer  finds 
that  about  one  hundred  of  such  strips  put  up  in  a  wide-mouth  tube  vial,  corked  and 
properly  labelled,  is  a  most  convenient  and  popular  form  for  general  use.    One  such  vial 
of  each  color  put  up  together  forms  a  pair  which  no  one  should  be  without;  and  most 
workers  will  buy  them  if  they  can  get  them.     These  convenient  'little  strips  may  be 
shaken  out  of  the  vial  as  wanted  for  use,  but  as  the  fingers  should  never  touch  any  other 
strip  than  the  one  taken,  it  is  best  to  take  them  from  the  vial  by  a  pair  of  forceps  from 
the  pocket  case." — DR.  EDWARD  L.  SQUIBB. 

128.  Every  one  who  undertakes  to  photograph  well,  should  possess  a  reasonably  good 
balance.    I  do  not  speak  here,  of 'course,  of  delicate  analytical  balances  turning  with  the 
hundredth  of  a  grain,  but  of  good,  common  balances  turning  on  knife  blades,  and  mov- 
ing immediately  with  a  quarter  of  a  grain.     And  I  may  remark  here  that  an  easy  way 
of  testing  this,  by  those  who  do  not  possess  fractional  weights,  is  by  cutting  up  pieces 
of  paper,  or,  better,  of  tin-foil.     If  a  nearly  square  piece  be  weighed  off,  weighing  four 


DAKK-ROOM    CONTRIVANCES.  277 

strticted  and  well  accoutred  dark-room,  it  should  be  his  pleasure  to  send  from 
it  the  best  possible  results.  To  this  end,  as  has  been  enjoined  previously,  he 
should  be  exact  in  weighing  and  measuring  his  preparations. 

grains,  and  the  smooth,  hard  letter-paper  or  the  tin  foil  be  cut  into  sixteen  equal  parts, 
we  have  so  many  quarter-grain  weights,  well  suited  for  testing  a  balance.  And  a  balance 
that  will  not  give  an  easy  and  decisive  indication  by  the  addition  of  such  a  quarter-grain 
fragment,  when  loaded  with  a  drachm  in  each  pan,  is  unfit  for  use. 

Another  important  point,  after  having  ascertained  the  sufficient  delicacy  of  the  balance, 
is  to  habitually  be  on  guard  against  sticking.  Neglect  of  this  point  has  led  to  thousands 
of  errors  in  weights,  and  vexatious  and  inexplicable  failures  in  the  operations  connected 
with  them.  "  Sticking  arises  from  this :  when  the  pans  are  not  far  from  equally  loaded, 
a  very  slight  cause  will  deprive  the  beam  of  freedom  of  motion.  It  may  not  rest  exactly 
square  on  its  supports,  or  some  grains  of  dust  or  other  foreign  body  may  have  got  on  the 
socket  under  the  knife-blade,  or  there  may  have  been  a  slight  tendency  to  rest.  Any  of 
these,  and  perhaps  other  causes,  may  preserve  the  beam  from  oscillating,  meantime  the 
needle  points  exactly  vertical,  and  the  weight  seems  to  have  been  correctly  taken,  when, 
perhaps,  it  is  wrong  by  enough  to  seriously  affect  the  next  steps  to  the  operations. 

The  only  sufficient  safeguard  against  this  dangerous  mistake,  is  never  to  take  a  weight 
with  the  needle  in  this  condition,  never  to  depend  upon  the  needle  pointing  directly  to 
the  centre  of  the  index,  but  always  to  make  the  needle  oscillate,  and  see  that  at  each 
oscillation  it  moves  to  an  equal  distance  on  each  side  of  the  centre,  as  far  to  the  right 
as  it  does  to  the  left.  With  a  needle  moving  freely,  and  passing  to  an  equal  distance  on 
each  side,  anything  like  sticking  is  impossible,  and  the  operator  feels  safe  that  his  weight 
is  correctly  taken,  provided  that  his  weights  are  correct. — M.  CAREY  LEA,  M.D. 

The  danger  of  mistakes  is  far  greater  with  measuring-glasses  than  in  weighing,  than 
most  persons  would  find  it  easy  to  believe,  but  it  may  be  proved  in  various  ways.  Any 
one  desirous  to  verify  his  measurements,  can  make  the  following  experiment :  measure 
off  at  once  16  ounces  of  water  in  a  16-ounce  graduate  and  pour  it  into  a  bottle ;  next  take 
a  1-ounce  graduate  and  measure  off  successive  ounces  from  the  portion  thus  placed  in  the 
bottle,  until  the  whole  is  consumed,  and  compare  the  result. 

The  surface  of  water  or  of  other  liquid  in  a  measuring-glass  is  not  plane  or  level,  but 
represents  a  parabolic  curve.  The  liquid  is  drawn  up  the  sides  of  the  glass  by  capillary 
attraction,  and  the  whole  surface  has  a  meniscus  curvature.  It  is  the  central  or  lower 
portion  of  this  curve  that  should  correspond  with  the  ruled  line  of  divisions  and  not  the 
upper. 

If  the  operator,  having  made  as  accurate  a  measurement  as  he  can,  changes  his  posi- 
tion so  as  to  alter  the  manner  in  which  the  light  falls  upon  the  glass,  he  will  find  that 
his  measurement  no  longer  appears  correct,  but  seems  to  be  more  or  less  than  right. 
What  was,  or  appeared  right  when  the  light  came  from  above,  is  no  longer  so  when  the 
light  comes  in  level  lines,  or  is  thrown  up  from  below.  Of  these,  the  best  results  are 
given  by  a  level  or  horizontal  light.  A  good  burner  on  a  level  with  the  eye  is  very  con- 
venient for  taking  measurements.  On  the  other  hand,  light  from  a  gas-burner  consider- 
ably above  the  observer's  head,  tends  to  very  incorrect  results. 


278         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

These  two  operations  though  simple,  are  nevertheless  the  sources  of  many 
blunders  to  those  who  have  not  paid  a  certain  amount  of  attention  to  the  ordi- 
nary causes  of  error. 

Another  matter  of  considerable  moment  is  the  holding  of  the  measuring-glass  perfectly 
perpendicular.  A  very  little  error  in  this  respect  will  quite  vitiate  the  results.  And  the 
evil  of  this  increases  directly  with  the  diameter  of  the  upper  surface  of  the  liquid  as  it 
stands  in  the  measuring-glass.  For  this  and  for  other  reasons,  narrow,  deep  graduates 
are  to  be  preferred  to  broader,  lower  ones. 

Narrow,  deep  vessels  of  a  cylindrical  shape  will  give  more  accurate  measurements  than 
those  that  are  conical,  and  are  much  used  for  exacter  work.  With  burettes  still  more 
accurate  work  can  be  done,  especially,  as  I  have  shown  elsewhere,  when  a  particular 
arrangement  is  used  for  making  correct  readings. 

Specific  Gravities. — The  combined  operation  of  weighing  and  measuring  gives  the  specific 
gravity  of  a  substance  which  represents  the  relation  of  weight  to  bulk.  This  determina- 
tion may  be  made  in  two  ways,  viz.,  by  ascertaining  the  weight  of  a  given  volume  of  the 
substance  (specific  gravity  bottle),  or  by  examining  its  buoyancy  (hydrometer). 

The  last  is  the  least  troublesome,  especially  when  a  number  of  specific  gravities  of 
liquids  are  to  be  taken,  but  the  first  is  by  far  the  more  accurate.  Not  only  is  the  reading 
of  the  hydrometer  less  exact,  but  a  great  many  of  them  are  very  carelessly  and  indiffer- 
ently made. 

It  is  hardly  safe  to  use  a  hydrometer  without  first  testing  it  with  a  specific  gravity 
bottle.  •  The  latter  is  a  small  vial  closed  with  a  tube  stopper ;  the  tube  has  a  capillary 
bore  like  that  of  a  thermometer,  the  liquid  being  poured  in  nearly  up  to  the  top  of  the 
neck,  the  stopper  is  inserted,  and  the  excess  of  liquid  escapes  through  the  tube-stopper 
and  is  wiped  off.  The  bottle  is  of  such  a  size,  that  when  filled  with  distilled  water  it  has 
a  given  weight  at  a  fixed  temperature,  generally  of  62°  F.,  though  sometimes  60°  or  70°. 
A  200-grain  bottle  or  a  10-gramme  may  be  considered  the  best  sizes.  The  only  precau- 
tions necessary  are  to  have  the  bottle  thoroughly  clean  inside  before  pouring  in  the 
liquid  to  be  tested,  and  to  wipe  the  outside  perfectly  dry  before  taking  the  weight,  hand- 
ling it  as  little  as  possible,  so  as  to  avoid  raising  the  temperature. 

The  specific  gravity  is  indicated  at  once  by  the  weight  of  the  liquid.  If  when  the 
100-grain  bottle  is  filled  with  nitric  acid,  the  weight  of  the  contents  proves  to  be  145 
grains,  this,  of  course,  indicates  a  specific  gravity  of  1.45.  Having  determined  the 
specific  gravity  of  any  liquid,  this  may  be  used  to  test  the  accuracy  of  hydrometers  by 
allowing  them  to  swim  in  it,  and  noting  the  indications,  and  how  far  they  are  correct. 

In  using  the  hydrometer,  care  must  be  taken  in  two  different  ways :  it  must  be  lowered 
gently  into  the  liquid ;  if  allowed  to  slip  quickly  in  it  will  sink  too  far  and  then  rise 
again  with  the  stem  wetted  above  the  line  of  the  liquid.  The  hydrometer,  having  thus 
an  extra  weight  to  carry,  will  give  an  erroneous  indication.  Also,  it  must  not  be  let  to 
touch  the  side  of  the  vessel,  or  it  will  be  held  there  slightly  and  not  move  freely. 

The  degree  should  be  read  off  by  looking  from  below  and  using  a  level  light.  Man- 
aged in  this  way,  results  of  tolerable  correctness  can  be  got,  but  not  equal  to  those  of  the 
specific  gravity  bottle. — M.  CAREY  LEA,  M.D. 


DARK-ROOM    CONTRIVANCES. 


279 


FIG.  285. 


FIG.  286. 


129.  Not  only  are  correct  measuring  and  correct  weighing  a  nicety  in  dark- 
room manipulation,  but  the  strength  of  the  solutions  should  be  carefully  main- 

Those  who  are  working  dry  processes  know  how  difficult  it  is  to  get  their  plates 
properly  dried,  and  at  the  same  time  to  keep  them  from  the  light,  and  free  from  foreign 
substances  tending  to  injure  them. 

The  following  diagram  of  a  drying-stand  for  dry-plates,  will  overcome  some  trouble. 
The  upper  connecting  piece  A  has  (If  inches  apart)  round  sticks  the  size  of  a  lead- 
pencil,  slightly  inclined  from  a  right  angle,  glued  to  it  as  shown  in  the  figure.    The  lower 
piece,  JB,  is  furnished  with  short  lengths  of 
glass  tubing,  also  If  inches  apart,  about  £ 
inch  diameter,  and  1£  inches  long,  to  receive 
the  lower  corner  of  the  plate,  and  convey  the 
drippings  to  a  trough  beneath,  which  is  sup- 
ported by  a  bent  wire  at  each  end.     This 
stand  may  be  fitted  in  a  box,  and,  when  the 
box  is  closed,  the  trough  should  be  removed. 
A  slip  or  tube  of  glass  runs  from  B  to  B,  and,  if  perfect  immunity  from  wood  is  desiredj 
glass  squares  can  be  fixed  on  the  projecting  arm,  thus  (see  Figs.  285  and  286)  : 

Of  course  there  are  dozens  of  modifications  possible. — ARTHUR 
GREEN. 

129.  It  often  happens  in  the  practical  everyday  working  of  a 
gallery,  that  it  becomes  necessary  to  know  the  strength  of  the 
several  solutions  of  nitrate  of  silver  employed. 

If  too  weak,  unsatisfactory  results  are  obtained,  and  if  too 
strong,  silver  is  uselessly  wasted ;  in  either  case  difficulties  arise 
which  are  frequently  attributed  to  other  causes. 

The  instrument  generally  used  to  give  this  information  is  the 
actino-hydrometer,  and  although  it  is  strictly  correct  in  the 
testing  of  pure  silver  solutions,  is  very  unreliable  when  these 
solutions  have  been  for  some  time  in  use.  It  is  noticed  by 
those  using  it,  that  a  bath  working  well  when  the  hydrometer 
indicates  forty  grains  to  the  ounce,  will  after  a  time  not  be  in 

the  same  good  condition  until  it  marks  forty-five  grains  or  more.     The  reason  of  this  is, 
that  this  instrument  shows  only  density  or  specific  gravity. 

It  is  well  known  that  different  bodies  of  the  same  weight  are  of  different  sizes,  and 
again,  that  bodies  of  the  same  size  have  different  weights,  as  for  instance,  a  pound  of 
lead  is  smaller  than  a  pound  of  wax,  and  a  piece  of  lead  weighs  more  than  a  piece  of  wax 
of  the  same  size.  When  the  weights  of  different  bodies  are  compared  to  the  weight  of 
equal  volumes  of  water  we  have  what  is  called  their  specific  gravity.  The  specific  gravity 
of  gold  is  19.3 — that  is,  1  cubic  inch  or  foot  of  gold  weighs  19.3  times  more  than  a  like 
bulk  of  water,  and  when  the  specific  gravity  of  an  acid  is  given  as  1.4  it  means  that  a 
cubic  inch,  or  a  pint,  or  any  other  measure  of  it  weighs  1.4  times  more  than  an  equal 
measure  of  water.  We  have  in  the  hydrometer  a  quick -means  of  finding  specific  gravities 


280 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


tained  at  the  proper  degree.     Frequent  tests  should  be  made  and  DO  heed- 
lessness  whatever  allowed. 

A  great  convenience  in  the  dark-room  is  plenty  of  clear,  pure  water,  and  a 
proper  arrangement  of  the  tanks,  with  a  means  of  saving  such  waste  as  is  of 
value,  and  of  getting  rid  of  the  rest  without  injury  to  the  health. 

There  are  some  persons  who  guess  even  at  the  condition  of  their  chemicals. 
I  believe  in  "  instinct,"  "  feeling,"  "  inspiration/'  and  whatever  you  choose  to 
term  it,  but  above  all  things  else  I  do  lean  on  thoughtful  care  in  doing  all 
things  well. 

It  is  simply  shocking  to  see  the  slovenliness  of  some  manipulators,  and  yet, 
they  are  the  very  ones  who  have  the  most  time  to  complain  of  their  results 
and  of  that  bugbear  "  Cheap  John." 

of  liquids.  If  we  float  it  in  different  densities,  it  will  sink  to  different  depths  in  them, 
but  always  so  far  until  the  weight  of  the  volume  of  displaced  liquid  equals  the  weight  of 
the  whole  instrument.  As  hydrometers  are  used  for  various  purposes,  the  scales  are 
divided  differently,  some  to  indicate  specific  gravity,  others  to  give  the  different  per- 
centage of  alcohol,  or  to  give  the  strength  of  acid,  etc.  As  the  same  liquid  varies  in 
density  according  to  its  temperature,  it  is  necessary  to  have  a  standard, 
which  is  usually  sixty  degrees  Fahrenheit,  and  all  solutions  should  be 
made  of  the  proper  temperature  before  testing. 

The  scale  of  the  actino-hydrometer  is  prepared  in  the  following 
manner :  It  is  first  floated  in  pure  water  at  sixty  degrees  Fahrenheit, 
and  the  point  to  which  it  sinks  marked  (this  is  the  zero  of  the  scale. 
Fig.  287.)  It  is  then  placed  successively  in  solutions  of  the  same  tem- 
perature containing  ten,  twenty,  thirty,  etc.,  grains  of  nitrate  of  silver 
to  the  ounce,  and  the  different  points  to  which  it  sinks  carefully 
marked.  These  points  are,  when  the  scale  is  to  indicate  one  grain 
for  each  degree,  the  ten,  twenty,  and  thirty  degrees,  etc.,  of  the  scale. 
The  intermediate  single  degrees  are  put  in  by  simply  dividing  off  into 
ten  equal  spaces.  This  instrument  thus  prepared  can  be  used  to  test 
any  other  pure  solution  of  a  soluble  salt,  but  as  these  solutions  vary 
very  much  in  density  when  containing  the  same  number  of  grains  of 
the  different  salts  dissolved  in  them  (for  example,  a  solution  contain- 
ing twenty  grains  of  chloride  of  ammonium  does  not  test  the  same  as 
one  containing  twenty  grains  of  hypo  soda)  a  table  of  corrections  is  required.  Such  a 
table  accompanies  Tagliabue's  actino-hydrometer.  The  instrument  has  no  discriminat- 
ing or  selecting  power,  hence  if  the  two  solutions  just  named  were  mixed  together,  no 
table  could  be  made  which  would  give  from  the  indication  on  the  stem  the  number  of 
grains  in  the  one,  and  the  number  of  grains  of  the  other  contained  in  each  ounce  of  it. 
When  a  silver  bath  is  new,  the  reading  of  the  hydrometer  can  be  relied  upon,  but  in 


FIG.  287. 


DARK-ROOM    CONTRIVANCES. 


281 


FIG.  288. 


A  man  who  is  slouchy  in  his  dark-room  will  exhibit  the  same  talent  under 
his  skylight — in  fact,  in  whatever  he  does.     Do  not  be  caught.     Form  correct 

working,  as  every  plate  extracts  silver  by  the  formation  of  iodide  and  bromide  of  silver 
in  the  collodion  film,  and  adds  nitrates  of  potassa,  cadmium,  etc.,  according  as  iodide 
and  bromide  of  potassa,  cadmium,  etc.,  have 
been  used  as  excitants,  we  have  an  impure 
solution  in  which  the  above  salts  as  they  in- 
crease its  density  test  by  the  hydrometer  as 
so  much  silver,  and  we  cannot  tell  from  its 
indications  how  much  nitrate  of  silver  alone 
it  contains.  The  older  the  bath,  the  more 
impure  the  solution,  and  the  more  unreliable 
this  manner  of  testing  becomes. 

There  are,  however,  methods  by  which  we 
are  able  to  ascertain  the  quantity  of  nitrate 
of  silver  in  any  solution,  pure  or  impure,  one 
of  the  most  accurate  of  which  is  the  one  in- 
troduced by  Dr.  Vogel.  His  "silver  tester" 
consists  of  a  stand  S,  a  burette  a,  two  pipettes 
p  and  F,  and  a  beaker  glass  G.  A  solution  of 
iodide  of  potassium  is  prepared,  containing 
1023.4  cubic  centimetres  of  water,  exactly 
10  grammes  of  pure  dry  iodide  of  potassium. 
100  cubic  centimetres  of  this  solution  preci- 
pitate 1  gramme  of  nitrate  of  silver,  so  that 
if  1  cubic  centimetre  of  a  silver  solution  is 
measured  off  and  tested,  every  cubic  centi- 
metre of  the  test  solution  used  gives  1  per 
cent,  of  nitrate  of  silver  (1000  cubic  centi- 
metres =  2.11  pints  and  1  gramme  =  15.4  grains).  This  prepared  solution  is  placed 
in  the  burette  a,  which  is  divided  off  into  cubic  centimetres,  and  furnished  with  a  pinch- 
cock  k.  The  pipette  p,  is  then  dipped  in  the  silver  solution  to  be  tested,  filled,  by  draw- 
ing with  the  mouth  at  the  upper  end,  to  the  mark  it  which  is  an  exact  cubic  centimetre, 
and  the  solution  allowed  to  run  into  the  glass  G.  Into  the  same  glass  G,  are  placed  1  or 
2  cubic  centimetres  of  prepared  nitric  acid,  using  the  pipette  F.  (This  nitric  acid  con- 
tains 1  grain  of  protosulphate  of  iron  to  every  2  ounces  of  pure  acid.)  And  finally  10  to  14 
drops  of  a  prepared  starch  solution  are  added.  (This  solution  is  made  by  rubbing  up  | 
oz.  of  starch  to  a  thin  paste  with  distilled  water,  pouring  it  into  12£  ounces  of  boiling 
distilled  water,  and  stirring  for  several  minutes ;  after  settling  for  a  few  hours,  the  clear 
solution  is  poured  off,  and  2£  ounces  of  pure  pulverized  nitrate  of  potassa  added,  when 
it  is  ready  for  use,  and  will  keep  undecomposed  for  about  six  weeks.)  The  solution  in 
the  burette  a  is  then  allowed,  by  pressing  open  the  pinch-cock,  to  run  into  the  glass  G, 
until  the  blue  color  which  is  produced  does  not  disappear  by  shaking,  but  remains  per- 


282        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

and  exact  habits  when  you  first  take  up  photography,  and  they  will  help  you 
right  through. 

manent.  With  a  little  care  at  the  close  of  the  testing,  a  single  drop  will  be  found  suffi- 
cient to  produce  this  permanent  blue  color.  A  simple  reading  of  the  number  of  cubic 
centimetres  of  solution  used,  gives  the  per  cent,  of  nitrate  of  silver.  Thus,  if  it  stands  at 
7|,  the  tested  silver  solution  contains  7|-  per  cent.,  that  is,  100  cubic  centimetres  of  solu- 
tion contain  7f  grammes  nitrate  of  silver,  which  is  equivalent  to  about  35  grains  to  the 
ounce. 

Dr.  W.  H.  Pile,  of  Philadelphia,  manufactures  a  "  volumetric  silver  test,"  which  is 
much  simpler  than  Dr.  Vogel's,  as  it  consists  of  but  a  single  tube,  and  is  almost  as  cor- 
rect. In  using  it,  it  is  only  necessary  to  fill  the  tube  (Fig.  289)  to  the  point  O 
FIG.  289.  with  the  silver  solution  to  be  tested.  Then  add  the  test  solution  (made  by  dis- 
solving 140  grains  of  well-dried  rock  salt  in  one  pint  of  distilled  water  at  60°  F., 
and  adding  to  the  clear  solution  2  grains  of  bichromate  of  potassa),  freely  at 
first,  afterwards  gradually,  closing  the  tube  with  the  thumb  and  shaking  well 
after  each  addition,  until,  after  allowing  the  precipitate  to  settle,  no  more 
cloudiness  is  produced  by  a  drop  of  the  test.  The  level  at  which  the  liquid  in 
the  tube  stands  gives  the  number  of  grains  of  nitrate  of  silver  contained  in  each 
ounce  of  the  solution. 

There  is  an  "  easy  method  of  testing,"  which  is  within  the  reach  of  every 
photographer,  the  only  articles  required  being  an  8  oz.  narrow-mouthed  bottle, 
a  graduate  glass,  and  some  common  table  salt. 

The  test  solution  is  made  by  dissolving  55  grains  of  well-dried  salt  in  one 
pint  of  water.  Measure  into  the  8  oz.  bottle  £  oz.  of  the  silver  solution,  and 
add  the  test  solution  to  it  carefully  from  a  clean  graduate  glass,  shaking  well 
after  each  addition,  until  no  cloudiness  is  produced.  If  it  takes  1  oz.  of  this 
solution,  it  contains  10  grs.  of  nitrate  of  silver  to  the  ounce;  if  2  oz.,  it  contains 
20  grs. ;  and  so  also  of  fractional  parts;  3$  oz.  show  31^  grs. ;  3£  oz.  35  grs.,  etc. 
As  every  1  oz.  of  solution  used  shows  10  grs.  of  nitrate  of  silver  to  the  ounce, 
it  is  only  necessary  to  multiply  the  number  of  ounces  and  parts  of  an  ounce  by 

10  to  give  the  required  result.   A  2  oz.  graduate  glass  is  the  best  size  to  use,  as  it 
is  so  graduated  as  to  show  £  oz.  readily;  and  as  every  £  oz.  of  test  solution  equals 

11  grs.  of  nitrate  of  silver,  this  test  is  sufficiently  accurate  for  all  practical  pur- 
poses.    If  about  the  number  of  grains  in  the  solution  is  known,  add  at  once 
nearly  the  required  quantity  of  the  test,  and  afterwards  small  quantities  at  a 
time.     Supposing  it  to  contain  about  40  grs.,  add  3£  oz.  of  the  salt  solution, 
shake  well,  and  towards  the  latter  part  of  the  process  it  requires  hard  shaking 
to  get  the  chloride  of  silver  to  precipitate  out  and  leave  the  liquid  clear.   Then 
add  from  an  exact  measured  ounce  about  i  oz.  at  a  time,  until  the  precipitation 
is  complete.     Add  the  quantity  used  to  the  first  3£  oz.,  multiply  by  10,  and  we 
have  the  number  of  grains  of  nitrate  of  silver.     It  frequently  happens  that, 

before  sufficient  of  the  salt  solution  has  been  used,  that  the  precipitated  chloride  of  silver 
is  quite  bulky,  but  when  shaken  up,  after  the  addition  of  the  last  required  quantity,  it 


DARK-ROOM    CONTRIVANCES. 


130.  And  last  of  all  conies  a  study  in  the  question  of  economies.  A  great 
deal  of  unnecessary  waste  of  the  precious  metals  may  occur  if  no  care  is  exer- 
cised to  prevent  it. 

becomes  much  denser  and  settles  rapidly  to  the  bottom ;  this  is  a  good  indication  of 
enough  solution  having  been  used.  One  or  two  trials  of  this  process  will  give  all  the 
experience  required  to  enable  any  one  to  do  it  easily  and  quickly. 

If  the  silver  solution  contains  ammonia,  an  ammonio-nitrate  solution,  as  it  is  termed? 
after  measuring  off  a  £  oz.  of  it  hito  the  8  oz.  bottle,  make  acid  with  a  little  pure  nitric 
acid,  and  then  proceed  in  precisely  the  same  way  as  above  explained. 

Dr.  Vogel's,  Dr.  Pile's,  and  the  "easy"  methods  cannot  be  used  if  the  solutions  contain 
salts  of  lead  or  mercury ;  but  as  these  salts  are  not  used  by  photographers,  it  is  not  neces- 
sary to  give  processes  by  which  such  solutions  can  be  tested,  requiring,  as  they  do,  some 
knowledge  of  chemical  manipulation. — JAMES  F.  MAGEE. 

130.  Now,  if  you  will  take  a  box  of  a  suitable  size,  minus  a  top,  and  set  your  bath 
into  it  (see  Fig.  290),  and,  just  as  soon  as  your  plate  is  dipped,  tip  it  (the  bath)  forward, 


FIG.  290. 


FIG.  291. 


SHOWING      THE 

POSITION   OF  PLATE 

WHILE  COATING. 


and  let  it  remain  in  that  position  until  you  are  ready  to  remove  it  to  the  plate-holder, 
you  will  be  astonished  to  see  how  free  from  pinholes  your  negative  will  be,  and  it  will 
save  you  an  immense  amount  of  filtering.  I  have  been  practising  this  plan  for  many 
years,  and  am  surprised  that  so  few  operators  have  adopted  it. — I.  B.  WEBSTER. 

"  I  have  made  a  little  apparatus  which  does  away  with  the  evaporating  of  the  silver 
solutions  in  order  to  get  rid  of  the  accumulated  alcohol.  It  consists  of  a  tall  bottle  to 
hold  the  solutions  to  be  decocted.  The  bottle  is  closed  by  a  stopper  perforated  by  two 


284        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Again,  time  may  be  economized  by  careful  attention,  in  time,  to  all  the 
matters  pertaining  to  the  work. 

A  good  rule  is  to  do  first  what  must  be  done  without  anxious  care  as  to  what 
must  follow.  Then  everything  will  be  done  on  time,  and,  as  a  rule,  well  done. 

Once  more,  do  your  best  and  leave  the  rest.  Worry  spoils  more  work  than 
bad  lighting,  in  some  studios.  Whatever  else  you  do — after  everything  else  is 
clean — don't  worry. 

I  have  given  a  good  deal  of  care  to  this  matter  of  dark-room  contrivances. 
I  have  selected  my  notes  from  a  large  experience  and  from  a  large  quantity  of 
material,  and  have  tried  to  suggest  only  what  is  of  real  help.  There  is  much 

holes,  through  which  one  short  and  one  long  glass  tube,  reaching  down  to  the  bottom, 
pass.  To  the  short  tube  an  india-rubber  tube  is  fastened,  and  the  other  end  of  it  is  con- 
nected with  a  barrel  full  of  water.  Now,  as  soon  as  the  water  is  turned  on,  the  air  is 
drawn  through  the  long  tube  and  bubbles  up  through  the  silver  solution,  removing  all 
the  alcohol  in  a  very  short  time.  This  sketch  (Fig.  291)  will  help  you  to  understand  it 
I  hope. 

"A  is  a  hole  to  insert  the  funnel  for  filling  the  barrel  with  water,  now  closed." — 
R.  BENECKE. 

A  glass  or  any  other  kind  of  straight-edged  bath-holder  without  a  lip  can  be  readily 
emptied  without  spilling  a  drop,  in  the  following  way : 

Take  a  strip  of  clean,  white,  tough  letter-paper ;  bend  it  around  one  edge  at  the  mouth 
of  the  bath,  and  above  it;  hold  it  very  tight  with  one  hand,  while  you 
FIG.  292.         manage  the  bath  with  the  other,  and  pour.     (See  Fig.  292.)     Try  it.     I 
use  the  same  strip  of  paper  over  and  over  again. — B.  W.  KILBURN. 

A  new  horizontal  filtering  tray  for  the  negative  bath  was  presented  to 
our  Society  by  Mons.  Guinet.  Under  the  ordinary  covering  was  adjusted 
an  upright  ridge  of  glass  to  within  an  eighth  of  an  inch  of  the  top ;  this 
ridge  was  perforated  with,  say,  four  or  five  holes,  of  a  bridge-like  shape. 
A  filter,  which  stopped  up  the  holes,  was  placed  on  the  back  of  this  ridge. 
The  silver  solution  is  now  put  into  the  tray ;  the  latter  is  then  immediately  brought  from 
a  horizontal  to  an  upright  position ;  the  bath  runs  over  the  ridge,  the  ordinary  covering 
for  such  trays  acting  as  a  reservoir,  and  keeping  the 
liquid  from  running  over.  The  tray  is  now  placed 
in  a  horizontal  position,  the  upright  ridge  prevent- 
ing the  silver  solution  from  coming  into  the  tray 
otherwise  than  by  passing  through  the  filter.  In  a 
few  minutes  the  liquid  will  be  found  on  this  side 
of  the  ridge,  and  the  bath  is  ready  for  use. — LEON 
VIDAL. 

Mr.  Kruse,  of  Berlin,  has  invented  an  ingenious  negative  numberer,  which  may  be  thus 
described:  A  small  benzine  light  (or  candle)  is  placed  in  a  metal  lantern,  so  constructed. 


DARK-ROOM    CONTRIVANCES. 


285 


FIG.  294. 


help  in  having  these  conveniences,  provided  they  are  properly  used,  kept  clean, 
and  not  allowed  to  serve  merely  as  dust  catchers.  Now  all  such  misfortune 
may  be  prevented  if  the  habit  of  "  squaring  up"  becomes  a  fixed  principle  and 
is  daily  followed  with  conscientious  care.  I  am  emphatic  about  this,  for  I 
know  how  much  good  results  depend  upon  the  careful  use  of  clean  dark-room 
contrivances. 

As  in  any  other  work,  so  in  the  dark-room,  the  photographer  should  look 
well  after  his  light  supply.  If  the  light  is  allowed  to  come  into  the  dark- 
room from  the  side,  it  should  be  from  a  window  sufficiently  low  and  suf- 
ficiently forward  to  enable  one  to  receive  a  good  light  underneath  the  plate 
when  held  for  development.  This  window  must  be  provided  with  shutters  or 
covers,  that  more  or  less  light  may  be  shut  out  as  desired.  I  need  scarcely  add 
that  every  particle  of  white  light  must  be  carefully  excluded. 

both  with  regard  to  the  admission  of  light  and  the  letting  out  of  smoke,  that  no  white 
light  can  escape.  One  side  of  this  lantern  is  made  light-tight  by  means  of  a  wooden 
box  attached  to  it,  and  this  box  contains 
the  contrivance  for  numbering  the  nega- 
tive. On  the  outside  of  this  box,  in  the 
right-hand  corner,  there  is  a  groove  cut, 
into  which  the  yet  unnumbered  negative 
can  be  inserted.  Close  to  the  edge  of  this 
negative — in  the  middle  of  the  side  of 
the  wooden  box — is  a  narrow  slit  parallel 
to  the  edge  of  the  negative  through  which 
the  light  issuing  from  the  lamp  within  the 
lantern  can  reach  the  negative.  This  slit 
is  covered  by  three  small  hoops  of  thin 
copper  sheathing  placed  together.  Two 
of  these  hoops,  or  bands,  have  on  them 
the  numbers  00  up  to  99,  the  third  one 
has  from  0  up  to  9,  and  these  numerals 
are  cut  as  patterns,  so  that  by  a  judicious 
turning  of  the  bands,  the  numbers  from 
00000  up  to  99999  can  be  seen  in  looking 
through  the  slit.  The  turning  of  both 
these  bands,  which,  numbered  from  00  to 
99,  form  the  last  four  figures,  is  caused 
by  moving  a  button  up  or  down,  by  which 
means  the  bands  referred  to  are  wound  off 

from  one  small  wooden  cylinder  on  to  another,  whilst  the  band  bearing  the  numbers  0  to 
9,  which  indicates  the  10-thousands  of  the  number,  is  changed  by  every  movement  of 


286 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


PIG.  295. 


The  dark-room  being  now  in  perfect  order,  with  all  its  contrivances,  we 
shall  proceed  to  put  it  to  practical  use. 

the  hand  from  10  to  10-thousand  numbers.     In  using  the  instrument,  the  light  is  shut 

off  by  means  of  a  red  glass  brought 
to  view  from  within  when  looking  for 
the  controlling  number ;  the  negative 
is  inserted  in  the  slit  before  men- 
tioned, and  then  by  a  sudden  turn  the 
red  disk  is  drawn  away.  The  expo- 
sure for  the  number  is  therewith  at 
an  end,  and  the  latter  appears  in  the 
development  black  upon  a  bright 
ground.  Mr.  Kruse  has  also  arranged 
the  apparatus  so  as  to  print  his  name 
and  title  upon  the  plates. — E.  S.  W. 

Photographers  sometimes  lack  the 
necessary  room  for  fixing  up  a  small 
laboratory.  M.  Enjalbert,  of  Mont- 
pellier,  has  forseen  this  case,  and  has 
remedied  it  by  the  construction  of  a 
closet  in  which  all  the  operations  be- 
longing to  negative  photography  can 
be  performed.  This  closet,  when  shut, 
does  not  take  up  more  room  than  an 
ordinary  piece  of  furniture  of  this 
kind.  We  see  that  we  have  here  every- 
thing that  is  necessary  for  making  the 
divers  manipulations,  for  holding  the 
products,  the  dishes,  recipients,  etc. 
Evidently  the  space  is  rather  limited, 
but  it  is  sufficient  for  the  photographic 

tourist,  and  the  closet  can  be  used  in  a  bedroom  or  in  an  ordinary  workroom.  During 
the  day,  light  may  come  from  outside  through  the  red  glass,  and  at  night,  or  if  the  closet 
is  in  a  damp  place,  it  maybe  lighted  by  a  lantern.  A  water-tight  tank  for  washings  and 
the  other  liquid  products  that  are  to  be  rejected,  is  in  one  of  the  corners  of  the  closet, 
and  another  reservoir  full  of  clean  water,  placed  on  an  elevation,  is  used  for  washing  or 
the  other  operations  requiring  a  flow  of  water. — LEON  VIDAL. 


CHAPTER    XIV. 


NEGATIVE-MAKING "  WET/7 

A  WONDERFUL  revolution  has  taken  place  in.  negative-making  during  the 
past  five  years.  The  devout  wishes  of  photographers  for  some  new  method 
that  would  enable  them  to  discard  the  much  slandered  nitrate-bath  have  been 
met  by  emulsion  photography,  which  now  takes  the  lead. 

Still  the  "  wet"  method  has  its  uses  and  its  votaries.  There  are  some  cases 
where  this  "  old  "  method  gives  the  best  results,  and  there  are  some  workers 
who  still  adhere  to  it  exclusively.  Concise  directions  for  making  and  finish- 
ing negatives  by  the  "  wet "  or  collodion  process  will  therefore  follow. 

132.  The  first  step  is  to  scrupulously  clean  the  glass  plate  for  the  reception 

132.  I  send  photographs  of  a  little  affair  I  have  got  up  for  cutting  off  varnish  from  old 
negatives,  also  for  soaking  new  glass.  I  think  I  have  got  just  the  thing  for  that  purpose. 


FIG.  296. 


FIG.  297. 


I  have  had  two  boxes  made  at  the  pottery,  one   < 
fitting  inside  of  the  other,  to  put  'the  glass  j 
in  on  the  edge  (Fig.  296).     Draw  up  the  in-  > 
side  box,  let  it  rest  on  the  two  ends,  as  you 


(  287) 


288        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

of  the  collodion  film.  Taken  from  the  boxes  in  which  the  glass  arrives  from 
the  factory  it  is  placed  in  a  strong  solution  of  concentrated  lye.  Afterwards  it 
is  washed,  and  then,  while  wet  from  the  top,  flowed  with  a  very  dilute  solution 

will  see  in  Fig.  297,  and  by  the  time  you  have  it  in  position  the  acid  will  all  be  out, 
having  gone  through  the  bottom,  which  is  perforated  with  holes.  Then  you  can  get  out 
the  glass  without  any  trouble ;  it  will  hold  glass  enough  to  run  an  ordinary  gallery  a 
week  these  times.  This  one  takes  in  an  11  x  14  glass. 

The  one  I  use  for  lye  has  a  wood  box  for  inside ;  for  acid  I  use  the  stone,  as  the  wood 
would  soon  eat  up.  It  is  not  necessary  to  case  it,  yet  it  costs  but  a  little  more,  and  shuts 
up  tight ;  you  get  no  smell  of  the  acid. — S.  ROOT. 

On  Albumemzing  Glass. — When  albumenizing  the  glass  was  first  proposed,  I  found  dif- 
ficulties, but  the  following  method  has  given  me  plates  perfectly  free  from  faults. 

Prepare  a  stock  solution  of  albumen  as  follows : 

The  whites  of  six  eggs. 

Strong  ammonia,  one  drachm. 

Shake  well,  with  a  few  pieces  of  broken  glass  in  the  bottle. 

In  a  stoppered  bottle  this  keeps  any  length  of  time,  indeed  improves  by  age. 

When  about  to  use,  take  eight  ounces  of  water,  and  add  to  it  thirty  drops  of  C.  P. 
nitric  acid ;  mix  well,  and  add  half  an  ounce  of  the  above  albumen.  Shake  well,  and 
filter  through  paper. 

Clean  the  plates  by  any  method,  flow  with  the  dilute  albumen,  and  dry  as  usual. 

The  plates  keep  indefinitely. — C.  F.  RICHARDSON. 

To  clean  glass  for  collodion  and  silvering,  rasp  off  the  edges  and  corners  with  a  wet  sand- 
stone (a  scythe  whetstone  is  just  the  thing),  drawing  it  at  an  angle  and  diagonally  from 
the  face  of  the  glass,  to  avoid  chipping  the  surface.  Whether  new  or  old  glass,  varnished 
or  unvarnished  valueless  negatives,  wash  thoroughly  in  clean  hot  water  and  immerse  in 
a  very  strong  solution  of  boiling  potash,  from  three  to  five  minutes,  or  longer  if  old  hard 
varnished  glasses.  Scrub  with  a  fine  broom  brush  upon  a  padded  board,  covered  with 
tightly  drawn  flannel,  in  clean  hot  water,  rinsing  thoroughly,  and  then  rinse  oifin  clean 
cold  water,  and  coat  before  dripping  with  thinned  albumen,  two  or  three  ounces  to  the 
pint  of  water,  from  newly  laid  eggs,  with  four  or  five  drops  of  aqua  ammonia.  Dry  and 
keep  from  dust,  moisture,  and  light,  chemically  clean.  Use  at  pleasure ;  time  will  not 
deteriorate. 

Remarks :  Glasses  having  upon  their  surfaces  pure  metals  as  silver,  copper,  gold,  or 
any  other  metal,  must  have  the  same  removed  with  the  proper  acid,  or  aqua  regia,  before 
using  the  potash :  but  all  glasses  prepared  according  to  the  foregoing  recipe,  can  have  no 
free  pure  metal  in  contact  with  their  surfaces. 

The  albumen  should  be  freshly  made  and  very  thin. 

Stock  solution  :  Whites  of  six  eggs,  water  six  ounces,  aqua  ammonia  one  ounce.  Dilute 
for  use. 

A  common  sheet-iron  bakepan  will  answer  to  boil  the  potash  in,  on  an  ordinary  cook- 
stove. 

Scatter  a  layer  of  edge  cuttings  of  various  lengths  from  common  glass,  of  the  size  of 


NEGATIVE-MAKING — WET.  289 

of  pure  albumen.  When  dried  and  freed  from  dust  or  adhering  particles  it  is 
quite  ready  to  receive  the  collodion  film. 

133.  In  the  pages  devoted  to  Theory  and  Chemistry  the  offices  of  collodion 
have  been  stated.  In  short,  to  obtain  a  combination  with  nitrate  of  silver  in 
solution  that  is  sensitive  to  light  and  will  hold  a  developable  image,  certain 
salts  must  be  introduced.  Collodion  serves  as  the  vehicle  which  carries  these 

an  oat  straw,  on  the  bottom  of  the  pan,  and  between  each  layer  of  glass,  to  prevent  con- 
tact of  surfaces. 

Keep  the  hands  clear  of  any  caustic  by  using  wooden  tongs,  and  a  little  skilful  manipu- 
lation, and  do  not  scratch  the  glass  in  the  least. 

Never  pack  glasses  together  flatwise,  nor  lift  them  so  that  one  rests  upon  another,  but 
let  each  support  only  itself. 

My  method  of  cleaning  glass  may  not  be  all  new,  and  may  not  be  the  best  known.  It 
is  the  best  I  know ;  the  simplest,  and  always  avoids  dirty,  foggy,  or  stained  glasses,  or 
peeling  off  of  the  film. — ALBERT  S.  SOUTHWORTH. 

The  Blanchard  Brush.— This  contrivance,  which  combines  in  an  eminent  degree  sim- 
plicity and  efficiency,  is  of  very  great  value  in  applying  various  kinds  of  photographic 
solutions.  It  was  originally  employed  in  applying  both  silver  solutions  and  developing 
solutions  to  enlargements  on  paper.  Besides  its  general  convenience  in  evenly  spreading 
the  solution,  it  was  found  of  special  value  in  the  process  of  development,  as  it  gave  to  the 
operator  a  kind  of  local  power  in  controlling  the  action  of  the  developer.  Where  a  mass 
of  shadow  required  great  depth  to  give  force  to  the  picture,  the  energy  of  the  develop- 
ment could  be  increased  by  a  little  manipulation,  and  a  little  nitrate  of  silver  added  with 
the  brush.  Its  latest  use  has  been  in  connection  with  the  application  of  preliminary 
coating  of  dilute  albumen  to  glass  plates.  All  difficulty  in  spreading  the  albumen  solu- 
tion, usually  a  troublesome  operation,  vanishes  when  this  brush  is  employed.  One  sweep 
of  the  brush,  which  may  be  made  of  any  width,  covers  the  plate  evenly,  without  irregu- 
larity, bubbles,  or  any  kind  of  drawback.  % 

The  brush  is  made  as  follows :  A  strip  of  plate  glass,  about  three  inches  wide  and  five 
inches  long,  is  provided.  On  one  end  is  fastened  a  loop  of  swansdown  calico — a  cotton 
material,  twilled  on  one  side,  and  with  a  long  plush-like  nap  on  the  other.  It  is  to  be 
obtained  at  any  large  draper's.  The  nap  side  must  be  outwards ;  two  thicknesses  will 
be  found  better  than  one;  and  the  loop  can  be  readily  fastened  to  the  end  of  the  glass 
by  a  small  elastic  band.— VALENTINE  BLANCHARD. 

133.  An  excellent  keeping  collodion  can  be  made  as  follows :  Pure  absolute  alcohol, 
35  fluidounces ;  concentrated  ether,  35  fluidounces ;  iodide  of  ammonium,  150  grains  ; 
iodide  of  cadmium,  150  grains;  bromide  of  potassium,  120  grains;  pyroxyline,  300  grains, 
or  more  if  necessary. 

This  should  be  set  aside  for  a  week  before  use,  and  will  keep  two  or  three  months,  and 
sometimes  longer  if  the  materials  are  pure.  My  many  experiments  have  led  me  to  the 
belief  that  the  iodide  of  cadmium  is  the  most  stable  of  all  the  iodides  at  present  manu- 
factured, and  the  iodide  of  iron  the  least  so.  In  fact,  a  collodion  made  in  whole  or  part 

19 


290         WILSON'S  QUARTER  CENTURY  IN   PHOTOGRAPHY. 

salts  to  the  proper  place  and  retains  them  there  during  the  after-processes 
necessary  to  complete  a  photograph. 

Formulae  for  making  collodion  are  very  numerous,  but  their  results  are 
practically  the  same — at  least  sufficiently  so  for  our  present  purpose. 

The  collodion  is  poured  from  a  vial  or  pourer,  and  by  motion  of  the  hand 
caused  to  flow  evenly  over  the  whole  surface  of  the  glass,  the  surplus  being 

of  iodide  of  iron,  becomes  worthless  for  all  practical  purposes  after  twenty-four  hours ; 
yet  it  is  the  most  extremely  sensitive  collodion  I  know  of  while  in  its  best  condition, 
which  is  only  for  an  hour  or  two.  The  iodide  of  ammonium  comes  next,  but  will  produce 
a  more  sensitive  collodion  in  less  time  than  any  other,  except  the  iron.  Its  keeping 
properties  are  small,  though  much  greater  than  the  iron  compound.  The  bromide  of  all 
the  bases  gives  better  keeping  qualities  to  collodion  than  the  iodides  of  the  same  base. 
It  follows,  therefore,  that  no  arbitrary  rule  can  be  laid  down  for  the  manufacture  of 
collodion  in  all  cases. 

Dissolve  the  iodide  and  bromide  in  the  alcohol,  and  the  bromide  of  potassium  in  a 
few  drops  of  water,  and  add  to  the  rest :  fmally  add  the  ether ;  after  again  shaking  well, 
filter  it  through  paper  and  set  it  aside.  This  is  the  stock  solution  and  will  keep  a  long 
time  without  detriment.  When  wanted  for  use,  take  of  the  iodizing  solution  sufficient 
to  last  for  two  or  three  days,  and  add  pyroxyline  until  it  is  of  the  proper  consistency, 
and  filter  clear  for  use.  Some  photographers  use  two  to  two  and  a  half  grains  of  potas- 
sium to  the  ounce  of  collodion  ;  this  is  worse  than  useless,  it  is  waste. — GEORGE  H. 
FENNEMORE. 

My  experience  has  been  that  a  collodion  properly  prepared  with  an  eye  to  its  keeping 
qualities,  and  bromo-iodized  with  the  salts  of  cadmium,  will  increase  its  sensitiveness 
for  at  least  nine  months,  and  at  the  end  of  a  year  I  found  no  diminution,  although  the 
color  of  the  negative  began  to  change  somewhat  to  a  grayer  tone,  yet,  without  any  appre- 
ciable loss  of  actinic  resistance.  But  I  found  I  could  increase  its  sensitiveness  by  the 
addition  of  one  grain  of  iodide  of  ammonium  to  each  ounce  of  collodion.  I  also  tried  if 
the  iodide  of  cadmium  would  have  the  same  eifect,  but  it  did  not.  The  effect  produced 
by  the  addition  of  a  little  iodide  of  ammonium  to  the  already  sensitized  collodion,  led 
me  to  considerably  modify  the  preparation  of  collodion  for  keeping,  and  with  the  most 
successful  result,  as  I  shall  explain  presently,  in  my  formula.  But  first,  a  word  or  two 
on  the  chemicals  used  in  the  manufacture  of  collodion.  This  is  a  subject  of  no  small 
importance  to  those  intending  to  make  a  collodion  intended  for  long  keeping.  It  is  not 
sufficient  to  make  it  as  you  generally  do,  merely  substituting  the  salts  of  cadmium  for 
those  of  any  other  base,  but  a  proper  appreciation  should  be  had  of  what  constitutes  the 
elements  of  destruction  in  each  chemical  used,  and  to  apply  the  test  before  mixing  them 
together. — GEORGE  H.  FENNEMORE. 

Which  side  of  the  glass  should  be  coated  ? 

When  plate-plass  is  used,  the  finest  and  most  perfect  side  should,  of  course,  be  selected. 
But  in  the  case  of  blown-glass,  most  of  which  is  perceptibly  bowed,  the  question  arises  : 
Should  the  convex  or  the  concave  side  be  coated?  Some  careless  operators  do  not  pay 


NEGATIVE-MAKING — WET.  291 

poured  off  from  one  corner  into  a  separate  vial.     The  film  quickly  dries. 
When  it  is  barely  "tacky"  to  the  touch  of  the  finger  it  is  ready  to  be  excited 
or  sensitized  by  immersion  in  a  solution  of  nitrate  of  silver,  called  the* "  bath." 
This  should  be  done  in  the  dark-room. 

134.  The  bath  solution  may  be  held  in  a  horizontal  dish  or  in  a  vertical 
vessel  open  at  the  top.     Unless  the  plates  are  very  large  the  last  form  is  the 
better.     When  the  collodion  is  set,  the  plate  is  placed  upon  a  dipper  and  low- 
ered into  the  exciting  solution  with  one  steady,  continuous,  but  not  sudden, 
motion.     There   it  should  remain,  according  to  the  temperature,  until,  on 
examination,  all  oily  or  irregular  lines  are  removed.     To  facilitate,  the  plate 
should  be  easily  "churned"  up  and  down  in  the  solution  while  the  sensitizing 
process  goes  on. 

When  about  to  remove  the  plate  from  the  solution,  slowly  lift  the  dipper 
and,  seizing  the  plate  in  one  hand,  allow  the  superfluous  solution  to  drip  back 
into  the  bath-vessel. 

Now  place  the  excited  plate  in  the  holder  of  the  camera,  the  film  side  next 
to  the  lens.  Everything  is  then  ready  for  the  exposure — for  catching  the 
image. 

135.  Before  further  procedure,  however,  let  us  have  a  fair  understanding  as 

any  attention  to  the  point  at  all,  but  coat  the  best-looking  side,  whether  it  be  convex  or 
concave.  Generally,  however,  the  concave  side  is  selected,  and  for  the  reason  that  then 
the  pressure  of  the  spring  in  the  frame  tends  to  correct  the  curvature,  whereas  if  the 
convex  surface  be  collodion ized,  the  pressure  tends  to  exaggerate  the  curvature. 

This  method  of  proceeding  is  quite  correct  for  portrait  work,  and  for  taking  the  fronts 
of  buildings;  in  a  word,  for  all  cases  where  the  centre  of  the  object  is  nearer  to  the  lens- 
than  are  the  sides  of  the  object. 

But  in  landscapes  it  most  commonly  happens  that  the  central  objects  are  more  distant 
than  those  at  the  side.  When  this  is  the  case,  it  is  evident  that  if  the  plate  has  been 
coated  on  the  concave  side,  then  its  curvature  greatly  increases  the  difficulty  of  getting 
the  whole  of  the  picture  into  focus  together.  Whereas,  if  the  plate  be  coated  on  the 
convex  side,  then  its  centre  is  brought  nearer  to  the  lens,  and  the  shorter  focus  of  the  dis- 
tant objects  is  favored  by  the  form  of  the  film. 

Consequently  no  general  rule  can  be  given  as  to  which  side  of  a  bowed  plate  should 
receive  the  collodion  ;  the  concave  side  being  best  for  one  class  of  objects,  the  convex  for 
another. — M.  CAREY  LEA,  M.D. 

134.  The  sensitizing  bath  must  be  prepared  from  re-crystallized  nitrate  of  silver,  and 
should  be  rendered  slightly  acid  in  order  to  produce  perfectly  transparent  shadows ;  too 
much  acid  exerts  the  same  injurious  effect  upon  the  negative  as  too  little.  One  part  of 
silver  dissolved  in  twelve  parts  of  water,  is  a  good  proportion  for  making  a  bath ;  a 
saturated  solution  of  iodide  of  potassium  is  prepared,  and  to  every  400  grammes  of  silver 


292        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

to  what  we  are  to  expect  to  see  in  a  first-class  negative.  The  answer  is  just 
the  same,  no  matter  what  method  we  adopt — "wet"  or  "dry." 

A  brilliant  negative  is  the  first  thing  needful  in  obtaining  brilliant  pictures. 
Every  possessor  of  a  portrait  album  must  have  remarked  how  comparatively 
few  of  the  pictures  in  his  collection  have  any  pretension  to  brilliancy.  Many 
photographs  are  sharp  and  full  of  detail,  but  at  the  same  time  dull  and  without 
vigor,  or  they  are  sharp  and  clear,  but  hard,  and  without  either  detail  or  half 
tone.  But  few  specimens  are  plastic  and  brilliant,  and  have  sufficient  gradation 
of  tone. 

A  process  by  which  brilliant  negatives  are  obtainable,  includes,  of  course, 
many  manipulations  with  which  the  experienced  photographer  is  perfectly 
familiar ;  but,  nevertheless,  to  the  general  reader,  a  recapitulation  of  the 
different  conditions  necessary  to  their  production  may  not  be  without  interest. 

The  great  source  of  failure  lies  in  the  thickness  of  the  film  which  forms  the 
image  upon  the  glass  plate.  The  negatives  of  many  excellent  photographers 
possess  a  certain  amount  of  thickness,  nevertheless  a  really  good  negative  should 
be  thin  and  perfectly  clear.  A  few  points  in  the  deepest  shadows  should  display 
clear  glass,  and,  in  certain  portions  of  the  high  lights,  an  almost  perfect  opaque- 
ness of  the  film  should  be  visible ;  and  between  these  two  extremes  there  should 

solution  is  added  one  drop  of  the  iodide  and  one  drop  of  strong  sulphuric  acid,  as 
follows :  Nitrate  of  silver,  30  grammes ;  distilled  water,  360  grammes ;  strong  sulphuric 
acid,  1  drop;  saturated  solution  of  iodide  of  potassium,  1  drop. 

If  the  water  and  chemicals  used  are  perfectly  pure,  this  bath  will  give  beautifully 
clear  negatives ;  but,  should  not  this  be  the  case,  and  there  is  formed  upon  the  picture  a 
gray  deposit,  capable  of  being  removed  by  the  finger,  the  bath  is  purified  with  a  solution 
of  caustic  potash,  2  grammes;  water,  100  grammes — which  is  added  by  drops  to  the 
silver  solution  (shaking  the  latter  the  while),  until  a  slight  turbidity  is  observed.  The 
bath  is  then  exposed  to  the  sun  for  a  few  hours,  or  to  open  daylight  for  some  time,  when 
a  black  precipitate  will  be  formed,  which  is  filtered  off.  For  every  100  grammes  of  bath 
is  then  added  1  drop  of  acidulated  water  made  by  mixing  10  grammes  of  sulphuric  acid 
with  100  grammes  of  water.  After  standing  for  some  hours,  the  following  test  should  be 
made:  Coat  a  plate  with  collodion,  sensitize  it,  and  let  it  drain  well;  develop  it  in  the 
ordinary  manner,  without  exposing,  and  wash  and  fix  the  plate  as  usual.  After  fixing, 
if  the  glass  is  not  perfectly  clear,  but  is  still  covered  with  a  thin,  light  deposit  which 
may  be  removed  by  the  finger,  a  few  more  drops  of  acid  must  be  added,  and  the  experi- 
ment repeated ;  too  much  acid  must  never  be  added  at  any  one  time,  and  care  must  be 
taken  that  the  plates  used  in  the  experiments  are  perfectly  clean.  As  the  deposit  upon 
the  plate  may  likewise  be  caused  by  the  action  of  light,  all  chemical  rays  must  be  care- 
fully excluded  from  the  dark-room. — EDWARD  L.  WILSON. 

Pure  silver  and  distilled  water  will  make  a  bath  which  will  not  require  sunning  or 


NEGATIVE-MAKING — WET.  293 

be  as  many  gradations  of  tone  as  possible.  If  few  half  tones  only  are  present 
in  the  negative,  it  is  impossible  to  obtain  a  brilliant  print  from  the  same,  as 
the  result  will  either  be  weak  or  hard,  according  to  the  difference  in  the  thick- 
ness of  the  film  in  the  lights  and  shadows. 

136.  Let  us  suppose 'that  a  picture  possesses  twenty  different  gradations  of 
tone ;  in  order  to  be  able  to  furnish  a  good  print,  the  negative  must  then  be 
composed  of  twenty  different  thicknesses  of  deposit,  which  are  visible  when  the 
image  is  seen  by  transmitted  light.  A  negative  which  begins  with  perfect 
transparency,  presenting  no  hindrance  whatever  to  the  light  in  the  production 
of  the  deepest  tones,  and  which  possesses  the  twenty  gradations  of  tone,  is 
capable  of  giving  a  perfectly  brilliant  result,  although  it  may  not  appear  very 
opaque  in  its  highest  lights.  But  if  the  deepest  shadows  are  covered  with  a 
deposit  equal  to  ten  gradations,  then  the  film  in  the  highest  lights  must  be  of  a 
thickness  equal  to  thirty  gradations  of  tone,  in  order  to  be  capable  of  producing 
a  good  print ;  if  the  film  in  the  highest  lights  is  equal  in  thickness  to  twenty- 
five  gradations  of  tone  only,  it  will  give  less  brilliant  pictures  than  the  nega- 
tive first  mentioned,  although  the  film  may,  at  first  sight,  appear  of  greater 
thickness. 

Underexposed  negatives  generally  give  hard  pictures  with  large  masses  of 
white  and  black,  and  without  detail  or  half  tones.  Overexposure  causes  a  gray 

boiling.  But  as  this  water  is  not  at  hand  often,  good,  soft  spring  water,  or  from  a  piece 
of  ice,  or  river  water,  will  do.  Put  one  or  two  ounces  of  silver  into  a  quantity  of  water 
sufficient  to  fill  your  bath-holder,  with  a  little  excess ;  place  it  in  the  sun  for  six  or  eight 
hours,  or,  what  is  just  as  well,  place  it  over  the  fire  in  the  evaporating-dish,  and  bring  it 
to  a  boiling  heat.  Either  method  will  throw  down  all  impurities  in  the  water.  Filter 
and  add  silver,  to  make  it  up  to  40  grains  to  the  ounce  of  water  by  the  testing-tube, 
which  everyone  should  have.  Not  more  than  40  grains  strong,  as  much  trouble  often 
meets  you  at  once  when  made  stronger. 

Coat  a  large  glass  plate  on  both  sides  with  collodion,  and  let  it  remain  in  the  bath 
over  night.  Filter  the  bath  again,  and  try  a  plate  ;  if  it  works  clear  and  clean,  add  no 
acid;  if  a  little  foggy,  add  two  drops  of  C.  P.  nitric  acid  to  50  ounces  solution.  Now, 
after  using  a  few  plates,  it  will  work  all  right,  and  should  not  be  altered  for  weeks,  unless 
it  be  to  add  more  of  the  same  solution  of  which  the  bath  was  made. 

If  you  work  with  care,  with  clean  plates  and  clean  fingers,  the  bath  will  not  need 
filtering  often  er  than  once  a  week,  or  once  in  two  weeks,  according  to  use.  It  is  a 
positive  evil  to  be  filtering  the  bath  every  day.  When  by  use  the  bath  works  oily  by 
excess  of  alcohol  and  ether,  but  well  otherwise,  add  a  little  alcohol  to  the  developer,  and 
use  the  bath  as  long  as  possible. — WILLIAM  SNELL. 

First  of  all,  work  the  bath  until  the, negatives  show  signs  of  pinholes  ;  then  remove  it 
from  the  holder  and  filter  half  of  it  in  the  dark.  Eeturn  to  the  holder  (which,  of  course, 


294        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

precipitate  to  cover  the  picture,  which  fogs  the  shadows ;  a  print  produced  from 
such  a  negative  is  too  light  m  the  shadows  and  too  dark  in  the  lights,  for 
everything  is  lost  in  half-tone,  and  brilliant  lights  and  deep  shadows  are  want- 
ing ;  in  an  overexposed  negative  a  black  coat  becomes  gray.  In  developing  a 
plate  which  has  been  exposed  too  long,  it  is  best  not  to  allow  the  developer  to 
go  too  far,  but  to  wash  the  plate  as  soon  as  symptoms  of  overdevelopment  are 
recognizable ;  in  this  manner  many  a  picture  may  be  saved. 

The  collodion  to  be  used  must  not  be  too  freshly  mixed,  and  should  be  per- 
fectly clear ;  its  consistence  should  not  be  too  thin,  and  it  must  be  sufficiently 
iodized.  Thick  collodion  should  be  diluted  with  equal  parts  of  perfectly  pure 
alcohol  and  ether. 

Since  so  much  is  entailed,  then,  in  securing  a  negative  of  the  proper  quality, 
it  is  incumbent  upon  the  photographer  to  exercise  the  utmost  care  and  attention 
in  all  details.  To  do  so  at  first  is  better  than  to  resort  to  after  manipulations. 

137.  Understanding  this  we  carry  the  ready  plate  out  into  the  light  for  ex- 
posure. When  we  bring  it  back  to  the  dark-room  it  will  hold  wondrous 
possibilities. 

We  have  so  carefully  studied  the  subjects  of  lighting,  posing,  and  exposing, 
in  and  out  of  doors,  that  for  our  present  purpose  not  even  an  exposure  upon 
paper  is  necessary.  We  will  imagine  that  it  has  been  made  and  properly  made, 
and  repair  to  the  dark-room,  full  of  curiosity  to  know  what  shall  come  forth 
from  the  mysterious  image  which  has  been  impressed  upon  the  still  wet  film. 

has  been  well  washed  in  the  interim),  and  add  to  it  an  equal  bulk  of  a  plain  forty-grain 
solution  of  nitrate  of  silver  dissolved  in  sunned  and  filtered  rain-water  to  which  a  little 
silver  has  been  added.  The  bath  is  now  ready  for  use,  and  will  be  found  to  give  nega- 
tives far  better  than  would  be  obtained  from  any  new  bath. 

The  remaining  half  of  the  old  solution  may  be  boiled  down  and  crystallized.  The 
crystals  are  washed  and  dried,  and  then  can  be  used  as  ordinary  crystals ;  for  when 
obtained  in  this  way  they  are  quite  free  from  iodide,  acid,  or  organic  matter. 

Do  not  let  it  be  supposed  that  I  condemn  sunning  the  bath,  for  this  is  not  the  case  ; 
but  if  a  bath,  either  all  or  in  part,  which  has  been  in  use  is  taken  into  the  light,  an 
action  is  at  once  started,  and  unless  that  action  be  allowed  to  go  on  until  completed  it  is 
hopeless  to  attempt  taking  good  negatives.  Therefore,  if  a  bath  is  intended  to  be  used 
again  directly  keep  the  light  from  it;  but  if  time  can  be  spared  give  it  all  the  light 
possible. 

About  filtering  a  bath ;  let  any  photographer  who  uses  paper  for  the  purpose  of 
cleansing  the  solution  properly  just  try  for  once  the  stuffing  of  the  funnel  with' cotton- 
wool (which  should  have  a  little  alcohol  and  ether  run  through,  and  then  washed  with 
•water),  and  see  the  difference  between  the  bath  filtered  so  and  through  paper. — W.  T. 
WILKINSON. 


NEGATIVE- MAKING — WET.  295 

138.  So  far  we  have  only  been  mixing  the  clay.  We  now  come  to  the 
moulding  stage.  We  should,  as  we  proceed,  bear  in  mind  all  the  points — the 
nature  of  our  subject,  the  condition  of  the  light,  the  temperature,  the  length  of 
exposure,  and  the  nature  of  the  solutions  employed  in  development.  Not  once 
should  the  thoughts  wander  from  the  work 

138.  Conditions  of  the  action  of  the  developer  are :  1.  The  presence  of  a  silver  solu- 
tion. 2.  A  certain  proportion  of  alcohol  and  acetic  acid,  in  order  to  facilitate  the  flow 
of  the  developer,  and  to  enter  into  the  film.  Thin  iodized  collodion  can  stand  but  a 
small  proportion  of  iron  (two  per  cent.).  Thick  iodized  collodion  requires  a  strong  de- 
veloper. Strong  developers  give  more  details  in  the  shadows  (they  work  softer),  while 
weak  developers  work  hard.  The  latter  are  better  suited  for  copying  line  drawings,  etc. 

Formulae  for  portrait  and  landscape  work :  Five  parts  of  sulphate  of  iron,  or  seven 
parts  of  sulphate  of  iron  and  ammonia ;  three  to  four  parts  of  glacial  acetic  acid ;  one 
hundred  parts  of  water  ; 

Or,  ten  parts  of  sulphate  of  iron,  or  fourteen  parts  of  sulphate  of  iron  and  ammonia; 
three  to  five  parts  of  alcohol;  two  hundred  parts  of  water;  two  drops  of  sulphuric  acid. 

For  drawings :  Five  parts  of  sulphate  of  iron,  or  seven  parts  of  sulphate  of  iron  and 
ammonia;  three  to  five  parts  of  alcohol;  two  hundred  parts  of  water;  one  drop  of 
sulphuric  acid. 

The  proportions  of  alcohol,  as  well  as  of  acid,  should  be  greater  with  a  bath  containing 
much  alcohol  than  with  one  freshly  made. 

It  is  very  convenient  to  keep  in  stock  a  saturated  solution  of  sulphate  of  iron,  or  a 
solution  of  one  part  of  iron  to  five  parts  of  water.  This  may  be  diluted  in  due  propor- 
tions, and  the  alcohol  and  glacial  acetic  acid  added  afterwards.  Sulphuric  acid  may  be 
added  to  the  saturated  solution  at  once. 

Ordinary  spring  water  is  suitable  for  making  the  developer.  (Water  which  is  too  hard 
requires  a  little  more  acetic  acid.)  Ordinary  alcohol  is  sufficiently  pure  for  developing 
purposes,  but  it  should  not  contain  too  much  fusel  oil. — DR.  H.  VOGEL. 

Compound  Developer. — I  have  worked  this  with  great  success,  finding  it  to  be  the  most 
intensely  working  developer  I  have  ever  used  :  Water,  40  ounces;  iron,  1£  ounce;  sul- 
phate of  copper,  £  ounce;  glacial  acetic  acid,  1J  ounce;  or,  about  11  ounces  of  acetic 
acid,  No.  8;  alcohol,  1J  ounce;  ammonia,  50  drops. 

It  requires  little  or  no  redeveloping  or  strengthening,  and  has  the  great  advantage  of 
allowing  you  to  keep  it  upon  the  plate  a  longer  time  without  fogging. — R.  J.  CHUTE. 

The  addition  of  organic  substances  to  the  developer  is  extremely  favorable  to  the  pro- 
duction of  brilliant  negatives.  The  three  following  formula?  are  recommended  : 

No.  1.  Sulphate  of  iron,  25  grammes;  loaf  sugar,  40  grammes;  glacial  acetic  acid,  15 
grammes ;  water,  500  grammes ;  alcohol,  15  grammes. 

No.  2.  Sulphate  of  iron,  10  grammes;  loaf  sugar,  40  grammes;  glacial  acetic  acid,  10 
grammes  ;  water,  400  grammes  ;  alcohol,  1  gramme. 

No.  3.  Sulphate  of  iron  and  ammonia,  22  grammes ;  gelatine,  1  gramme ;  glacial  acetic 
acid,  8  grammes ;  water,  300  grammes. 


296        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  plate  is  now  taken  into  the  hand  from  the  plate-holder  and  held  by  one 
corner,  over  the  sink.  With  quick  and  skilful  hand  the  developing  solution  is 
poured  upon  the  film,  and  with  one  motion  caused  to  spread  over  the  whole 
surface  of  the  plate. 

With  regard  to  the  latter,  the  gelatine  is  dissolved  in  the  acetic  acid  and  50  grammes 
of  water  (this  will  take  several  hours),  apd  the  sulphate  of  iron  dissolved  in  250  grammes 
of  water,  and  both  solutions  are  then  mixed.  In  general  it  will  be  found  that  weak  de- 
velopers produce  opaque  negatives,  and  strong  developers,  negatives  of  a  harmonious 
character.  No.  2  developer  is  suitable  for  summer  work  and  for  strongly-lighted  pictures. 
The  developer  should  be  used  sparingly,  for  the  employment  of  too  much  solution  impairs 
the  brilliancy  of  the  negative. — L.  STERNBERG. 

The  developer  must  harmonize  with 'the  general  use  of  the  light.  That  is,  the  same 
proportions  would  not  answer  for  an  open  skylight,  or  one  where  the  light  is  subdued  by 
passing  through  thin  curtains,  or  a  ground-glass,  or  one  of  a  southern  exposure.  In  each 
one  of  these  the  light  is  of  a  different  value,  therefore,  the  relative  proportions  of  iron, 
acetic  acid,  and  water  must  necessarily  vary,  that  harmony  may  be  secured.  Iron  deposits 
the  silver,  acetic  acid  simply  retards,  therefore,  it  is  very  essential  that  these  should  be 
in  that  proportion  that  accommodates  the  best  use  of  either  of  the  above-mentioned 
skylights. 

Taking  a  nitrate  bath  nearly  free  from  alcohol,  and  an  open  light,  1  ounce  of  sulphate 
of  iron  to  24  ounces  of  water,  and  sufficient  acid  to  cause  it  to  flow  quite  freely.  One 
ounce  will  do  it.  Let  this  proportion  be  the  thermometer  of  the  bath.  When  it  refuses 
to  flow,  do  not  add  more  acid,  but  change  the  bath.  As  the  plate  receives  the  first  lighting 
under  the  skylight,  so  it  receives  the  second  under  the  developer.  That  is,  by  the  man- 
ner of  manipulating,  it  can  be  made  harsh,  too  intense,  streaked  and  stained,  fogged,  flat, 
without  detail,  too  soft,  with  too  much  detail ;  all  these,  and  yet  the  same  can  be  made 
just  right,  in  every  respect  a  good  negative  by  the  right  handling.  One  cannot  consis- 
tently be  changed  without  the  other,  so  the  bath  must  be  consigned  to  hotter  regions  to 
evaporate.  In  nine  cases  out  of  every  ten  it  will  be  just  at  that  time  when  also  the  excess 
of  iodide  needs  removing. — G.  F.  E.  PEARSALL. 

A  new  developing  process,  requiring  little  or  no  intensifying,  is  as  follows  : 

Protosulphate  of  iron,  2  drachms ;  sulphate  of  copper,  1  drachm ;  water,  10  ounces. 
When  dissolved,  add  ordinary  alcohol,  4  drachms ;  glacial  acetic  acid,  2  drachms ;  liquor 
ammonia,  20  drops.  Shake  well  and  filter. 

If,  instead  of  the  protosulphate  of  iron,  ammonio-sulphate  of  iron  be  used,  then  the 
liquor  ammonia  is  not  required. 

If  the  sulphate  of  copper  be  found  to  dissolve  too  slowly,  its  solution  will  be  accelerated 
by  being  placed  in  warm  water. 

Should  it  prove  requisite  to  intensify  the  negative,  the  following  may  be  used  : 

Distilled  water,  1  ounce;  pyrogallic  acid,  4  grains;  citric  acid,  3  grains.  To  be  mixed 
in  equal  portions  with  the  following:  Distilled  water,  2  ounces;  nitrate  of  silver,  10 
grains ;  glacial  acetic  acid,  2  drops. — WILLIAM  MAcNiCHOL. 

If  we  attempt  to  stop  development  on  a  fully  exposed  plate,  before  it  has  reached  its 


NEGATIVE-MAKING — WET.  297 

Impatience  is  soon  relieved.  The  whites,  or  such  parts  of  the  subject  as 
have  received  the  most  light,  first  make  their  appearance,  and*  are  followed  by 
the  shadows  and  their  details. 

The  result  is  the  appearance  of  the  latent  image,  which,  however,  is  negative 
— i.  e.,  the  parts  which  are  light  in  nature  are,  by  transmitted  light,  dark  or 
dense  in  the  film,  and  vice  versa. 

full  intensity,  streaks  and  stains  will  be  sure  to  form  if  we  do  not  pour  on  an  abundance 
of  water,  and  keep  the  plate  wholly  covered  until*  the  oily  appearance  of  the  film  has 
nearly  disappeared,  and  there  is  no  longer  any  difficulty  in  keeping  the  film  covered 
with  a  small  quantity  of  water. 

In  photographing  landscapes,  it  is  often  of  the  first  importance  to  carry  as  little 
weight  of  material  as  possible,  and  the  necessary  supply  of  water  adds  greatly  to  the 
load.  The  appearance  of  the  plate  spoken  of  is  caused  by  the  difficulty  with  which 
pure  water  mixes  with  a  solution  containing  alcohol.  The  remedy  is  simple.  If  an 
equal  amount  of  alcohol  to  that  contained  in  the  developer  is  added  to  the  wash-water, 
one-quarter  drachm  per  ounce  or  more,  then  with  practice  and  care,  one  ounce  can  be 
made  to  go  as  far  as  a  pint  of  ordinary  water,  for  the  purpose  indicated.  The  "  crawling" 
of  the  developer,  or  of  the  wash-water,  will  be  increased  by  adding  too  much  alcohol. 
Where  the  use  of  gelatine  in  acetic  acid  is  indicated,  as  in  copying  drawings,  the 
developer  flows  over  the  plate  without  a  break,  though  no  alcohol  is  added.  In  this  case 
alcohol  is  not  required  in  the  wash-water. 

I  had  devised  this  expedient  for  landscape  photography  before  the  publication  of 
Robinson's  method  with  golden  syrup.  There  are  some  difficulties  with  the  latter  that 
make  it  well  to  combine  the  two  methods.  First,  if  the  plate  has  had  a  full  exposure, 
it  is  impossible  to  cover  its  whole  surface  at  once  with  the  preservative,  and  thus  stop 
development  on  all  parts  alike,  and  stains  result  unless  we  dash  it  over  the  plate,  and 
thus  use  more  bulk  of  it  than  we  would  have  to  of  the  water  and  alcohol  mixture,  on 
account  of  the  viscid  nature  of  the  syrup ;  even  if  it  contains  its  proper  proportion  of 
alcohol.  There  is  a  second  difficulty ;  many  samples  of  commercial  molasses,  perhaps 
all,  contain  chlorides.  In  two  samples  this  was  so  much  the  case,  that  a  curdy  precipi- 
tate of  chloride  of  silver  was  formed  when  it  was  poured  on  the  film,  and  this  remained 
in  part,  firmly  adherent,  and  became  discolored  by  diffused  light,  and  left  numerous 
dark  spots  after  fixing.  The  best  plan,  under  the  circumstances,  seemed  to  be  to  first 
wash  off  the  developer  with  the  alcohol  and  water,  then  to  flow  on  the  syrup  mixture, 
when  no  curds  formed,  since  the  silver  had  been  washed  off.  Then  "golden  syrup"  was 
useful  to  keep  the  plate  moist  until  an  abundance  of  water  could  be  obtained  for  fixing, 
and  but  a  small  quantity  of  the  syrup  was  required. — JOHN  M.  BLAKE. 

The  development  of  a  negative  requires  both  mechanical  skill  and  a  keen  perception  of 
the  requirements  of  the  occasion. 

Lines  may  occur  on  the  negative  by  the  stoppage  of  the  developer  when  poured  over 
the  exposed  plate.  The  stoppage  is  generally  the  result  of  carelessness,  or  of  the  drying 
of  the  film  after  removal  from  the  bath.  In  the  latter  case,  more  of  the  developer  must 


298         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

If  success  has  rewarded  us,  our  result  is  agreeable  to  the  suggestions  made 
in  135,  136,  and  137.  To  hold  it  so,  it  must  be  cleansed  of  the  superfluous 
chemicals  still  adhering  to  the  film,  and  at  the  same  time  it  will  be  "  fixed." 
Thorough  washing  must  take  place  between  development  and  fixation. 

139.  Two  ingredients  are  employed  for  fixing  negatives,  namely,  cyanide  of 
potassium  and  hyposulphite  of  soda.  The  former  is  very  poisonous,  and  its 
use  should  be  avoided. 

be  taken  to  enable  the  plate  to  be  properly  flooded.  The  free  nitrate  of  silver  having 
partially  dried  on  the  film,  but  little  will  be  carried  away  by  the  developer  over  the  edge 
of  the  plate.  The  defect  may  also  arise  from  the  repulsion  of  the  free  nitrate  of  silver  on 
the  film  from  the  developer,  either  through  excess,  or  the  contrary,  of  alcohol. 

Lines  may  also  be  caused  by  leaving  a  small  quantity  of  water  in  the  developing-cup. 
This  will  not  readily  mix  with  the  alcoholic  developer,  and  will  cause  development  to 
be  delayed  on  portions  of  the  negative. 

That  the  image  is  poor  and  flat  may  arise  from  washing  off  the  free  nitrate  of  silver 
from  the  plate  by  the  developer ;  from  the  use  of  too  strong  a  developer ;  or  from  the 
bath  or  collodion,  as  already  explained. 

In  addition  to  negatives  becoming  hard  from  the  collodion  or  bath,  they  may  have  the 
same  defect  from  the  use  of  a  weak  developer ;  from  one  with  too  much  acid  in  it ;  or 
from  underexposure.  The  first  two  causes  may  arise  from  the  protosulphate  of  iron 
changing  to  persulphate. 

When  the  developer  refuses  to  flow  evenly  over  the  film,  and  seems  to  be  repelled  by 
it,  either  too  much  or  too  little  alcohol  has  been  added. 

A  scum  on  the  developer,  formed  during  development,  may  denote  a  want  of  acetic 
acid.— JOHN  L.  GIHON. 

139.  In  fixing  a  picture,  whether  we  use  cyanide  or  hypo,  much  the  safest,  cleanest,  and 
most  economical  plan  is  to  have  a  dipping-bath.  If  cyanide  be  used,  it  has  less  chance 
of  getting  into  any  stray  cuts  or  scratches  we  happen  to  have  on  our  hands  or  fingers — 
sometimes  very  troublesome,  perhaps  dangerous — not  to  speak  of  the  poisonous  fumes 
inhaled  when  pouring  it  on,  or  when  immersing  the  plate  in  an  open  dish.  I  think  most 
photographers  would  give  the  preference  to  hyposulphite  of  soda  for  fixing  if  they  were 
not  afraid  of  having  it  near  their  baths.  But  if  it  be  kept  in  another  place — as  it  is  not 
necessary  to  have  either  of  the  fixing  agents  in  the  dark-room — it  has  this  good  advan- 
tage over  the  cyanide,  thaj  it  does  not  seem  to  thin  down  the  negative  nearly  so  much  as 
the  cyanide,  being  less  energetic  in  its  action,  and  I  think  it  also  leaves  the  negative  of  a 
better  printing  color.  A  point  very  often  neglected,  and  which  is  very  necessary  to  aid 
in  securing  clean  pictures,  sometimes  saving"  a  world  of  trouble,  is  to  make  it  a  habit^ 
after  developing  or  fixing  a  picture,  to  rinse  the  hands  in  clean  water,  and  dry  them 
carefully  on  a  cloth  kept  for  that  purpose :  it  will  help  to  keep  our  tempers  sweeter,  and 
leave  us  in  a  more  amiable  mood  than  if  we  discovered  sundry  smears  and  smudges  under 
the  collodion  film,  on  coating  or  developing  the  next  plate,  which  our  now  chemically- 
clean  fingers  had  something  to  do  with. — ANONYMOUS. 


NEGATIVE-MAKING  —  WET.  299 

A  saturated  solution  of  hyposulphite  of  soda  is  best.  The  plate  should 
remain  therein  until  all  appearance  of  yellowness  disappears  and  the  image 
looks  clean  and  clear. 

140.  Thorough  washing  in  changing  water  should  follow  fixation,  after 
which  the  plate  is  placed  in  a  rack  or  edged  on  a  support  and  allowed  to 
become  absolutely  dry. 

Where  running  water  is  not  obtainable,  then  the  wash  water  should  be 
entirely  changed  several  times  during  the  operation  of  washing. 

The  washing  should  be  continuous  also.  If  a  negative  becomes  entirely 
dry,  or  partly  dry,  no  further  washing  will  do  it  any  good.  The  hyposulphite 
should  be  thoroughly  washed  from  the  film  if  all  risk  of  discoloration  and  loss 
is  to  be  avoided. 

As  some  have  complained  of  the  destruction  of  negatives  fixed  with  hyposulphite  of 
soda  by  time,  a  correspondent  of  the  News  brings  forward  a  case  in  which  a  set  of  nega- 
tives, ten  years  old,  fixed  with  hypo,  were  found  in  excellent  order. 

No  possible  danger  can  arise  from  fixing  with  hyposulphite,  if  it  be  perfectly  washed, 
and  this  washing  out  will  always  require  a  certain  time,  no  matter  how  rapid  the  current 
of  water  may  be.  When  water  is  scarce,  so  that  a  stream  ca»not  be  kept  up  for  the 
needful  time  (five  to  ten  minutes,  according  to  size),  it  is  better  to  distribute  the  water 
into  four  or  five  pans,  and  let  the  negative  lie  five  or  ten  minutes  in  each  in  succession. 
The  last  pan,  or  even  two  pans  of  one  negative,  might  be  used  to  begin  the  next  with. 
Where  a  stream  is  used,  of  course  particular  care  must  be  taken  that  a  ripple  forms  on 
every  part  of  the  film,  to  make  sure  that  the  water  is  everywhere  in  active  motion.  Even 
with  this  precaution,  however,  time  is  needed,  because  the  film  is  not  like  the  blotting- 
paper,  from  which  solutions  can  be  "displaced,"  but  it  is  like  membrane,  from  which 
liquids  must  be  removed  by  osmose,  which  is  always  far  slower  in  its  action  than  dis- 
placement. 

140.  The  course  of  washing  a  negative  is  not  often  observed,  but  it  is  interesting  to 
notice  the  action  of  the  water  when  received  upon  a  levelled  plate.  The  current,  from 
the  spot  where  the  water  impinges  on  to  the  film  to  the  edges,  does  not  seem  to  act  upon 
the  whole  of  the  liquid  present;  for,  if  a  spot  of  dust  or  other  floating  particle  be  observed, 
it  will  be  noticed  that  it  does  not  instantly  disappear  from  the  plate  in  the  current  of 
moving  water.  We  have  watched  such  a  floating  mote  upon  a  negative,  and  have  seen 
it  retain  its  place  for  a  considerable  time,  till,  if  the  plate  were  slightly  tilted  and  the 
stream  directed  to  one  end  of  the  plate,  it  immediately  disappeared.  To  our  mind  the 
hand-washing  is  far  the  better  plan,  if  there  be  convenience  for  having  it  so  done ;  but, 
failing  that,  we  should  prefer  a  continuous  stream  sweeping  along  a  levelled  plate 
from  end  to  end  for  a  much  longer  time  than  is  usually  considered  necessary. — British 
Journal. 


300 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


141.  Tp  protect  the  still  delicate  film  from  abrasion  during  the  process  of 
printing,  the  plate  must  next  be  varnished.  This  operation  should  be  per- 
formed .in  a  room  free  from  dust.  The  plate  should  be  warmed,  then  the 
varnish  poured  upon  it  and  sent  over  the  whole  surface  the  same  as  collodion. 

Fig.  298  shows  a  "washing  apparatus"  of  my  own  invention,  which  gives  the  most 
perfect  satisfaction. 

FIG.  298. 


G' 


A  varnished  zinc  dish,  A,  contains  the  pictures  destined  to  be  washed,  after  having 
been  submitted  to  the  hyposulphite's  action  and  a  salt-water  washing.  At  ten  centi- 
metres from  the  bottom  of  the  dish  is  placed  a  horizontal  bored  plane,  on  which  are  settled 
the  pictures.  The  upper  side,  D,  is  composed  of  a  double  dish  at  balance.  When  the 
reservoir,  E,  which  is  located  under  the  water-spout,  is  full,  it  will  fall  on  the  repair,  F, 
and  sooner  tenders  the  other  to  receive  the  water.  The  motion  that  consequently  follows 
will  singularly  help  to  despoil  the  pictures  from  hyposulphite.— A.  BETTINI. 

141.  My  proportions  for  varnish  are  as  follows:  Bleached  lac,  10  drachms;  picked 
sandarac,  5  drachms ;  alcohol,  12  fluidounces. 

Leaving  out  the  sandarac,  I  let  the  lac  dissolve  as  completely  as  it  will,  and  then 
filter  it  through  paper.  Take  rather  a  large  filter,  soak  it  thoroughly  with  clean  alcohol 
before  pouring  in  the  varnish,  or  the  fine  stuff  will  at  once  choke  the  pores  of  the  paper 


NEGATIVE-MAKING  —  WET.  301 

The  varnish  should  be  hard  and  dry  before  the  negative  is  handed  to  the 
printer. 

Varnishes  of  excellent  quality  are  sold  by  the  supply  merchants.  Those 
who  use  but  little  will,  find  its  purchase  more  economical  than  manufac- 
turing it. 

and  stop  the  filtration.  Pour  off  quietly  so  as  to  keep  the  thicker  parts  for  the  last. 
Cover  up  the  funnel  with  a  glass  plate.  The  last  portions  may  be  thinned  with  an 
ounce  or  two  of  alcohol  to  enable  them  to  get  through,  and  still  leave  sufficient  body. 

Next  add  the  sandarac  to  the  filtrate,  and  filter  again.  This  second  filtration  is  no 
trouble  at  all,  as  the  varnish  goes  through  like  so  much  water  (of  course,  a  fresh  filter  is 
to  be  used). 

To  apply  the  varnish  made  according  to  the  foregoing  formula,  the  plate  is  to  be 
slightl7  heated,  for  which  a  Bunsen's  burner  answers  perfectly. 

The  bottom  of  the  plate  should  be  pleasantly  warm  when  felt  by  the  edge  of  the  right 
hand  (the  lower  part  of  the  thumb  and  side  of  the  hand),  not  hot.  The  varnish  is 
poured  on,  tilting  the  plate  first  forward,  then  backward,  alternately,  till  it  is  covered, 
so  that  the  pool  of  varnish  shall  continually  spread  in  all  directions.  If  any  smoke 
rises,  the  plate  was  much  too  hot.  The  plate  is  tilted,  the  varnish  poured  off  into 
another  bottle  and  held  vertically  for  a  minute  till  the  varnish  sets.  Holding  before  a 
stove  to  dry  is  perfectly  useless,  and  only  increases  the  labor. — M.  CAREY  LEA,  M.D. 

A  cheap  little  article  for  keeping  varnish  clean  can  be  readily  understood  by  looking 
at  the  annexed  cut  (Fig.  299).    A  is  a  toy  teapot,  0  is  a  small  tin  funnel,  made  to  fit 
neatly  in  the  top  of  the  teapot,  B  is  a  strip  of  tin,  covering  about 
half  of  the  top  of  the  funnel.     In  using,  pour  from  the  spout,  and  FIG.  299. 

drain  the  plate  into  the  funnel  in  which  some  cotton  has  been 
placed.— O.  I.  C. 

I  feel  that  I  must  revert  once  more  to  the  question  of  trans- 
parency.    To  my  mind,  the  influence  of  varnish  is  always  regret- 
table, and  therefore  the  less  that  varnish  changes  a  negative,  the 
better.     Few,  I  think,  appreciate  how  much  varnishes  can  differ 
in  this  respect.     I  have  in  my  possession  a  commercial  varnish 
much  used  here,  which  works  with  remarkable  ease  and  smooth- 
ness, requires  no  heat,  and  leaves  a  surface  the  smoothness  and  polish  of  which  cannot 
probably  be  equalled  by  any  spirit- varnish  (it  appears  to  be  made  with  benzole).     But 
it  reduces  the  image  more  than  any  varnish  that  I  have  compared  ic  with. 

One  reason  that  photographers  do  not  generally  appreciate  these  differences,  lies  in 
the  fact  that  it  is  difficult  to  measure  in  any  given  case  what  effect  has  been  produced, 
in  comparison  with  what  would  have  been  produced  in  the  same  case  supposing  a  different 
varnish  had  been  employed.  But  the  comparison  is  easily  and  exactly  made  in  the 
following  simple  manner : 

I  take  the  finest  and  thinnest  French  letter-paper,  cut  a  number  of  pieces  of  a  con- 
venient size,  pour  out  the  varnish  into  a  clean  pan,  plunge  the  paper  completely  under 
it  for  a  half  minute,  and  then  dry  it,  either  cold  or  hot  as  the  case  may  require.  This  I 


302        WILSON'S  QUARTEK  CENTURY  IN  PHOTOGRAPHY. 

Thus  far  we  have  assumed  that  our  operations  have  been  successful.  Cases 
will  occur,  however,  where  the  negatives  will  need  after-treatment,  intensifica- 
tion or  reduction,  and  sometimes  more  or  less  retouching.  All  these  processes 
will  receive  attention  further  on. 

142.  The  principal  annoyances  which  beset  the  wet-plate  maker  arise  from 
a  disordered  condition  of  the  nitrate  bath,  from  the  collodion  film,  or  from  the 
two  together. 

The  main  troubles  to  be  met  with  from  the  bath  are  fog,  pin-holes,  weakness, 
and  markings  upon  the  film. 

repeat  with  each  varnish  to  be  tried.  The  difference  in  the  opacity  of  the  paper  after 
this  treatment  gives  an  excellent  indication  as  to  the  properties  of  the  varnish.  I  inclose 
some  specimens  of  paper  so  treated.  Those  marked  C  have  been  treated  with  the  com- 
mercial varnish  before  spoken  of,  and  those  marked  L,  with  that  here  recommended. 
The  marked  difference  in  the  effect  will  be  observed.  Those  that  are  dried  with  heat 
are  so  marked,  and  can  be  compared  accordingly. — M.  CAREY  LEA,  M.D. 

Removing  varnish  from  old  negatives  is  very  easy  and  speedily  done.  Make  a  wooden 
tray  14  x  18  inches  square,  6  inches  deep,  watertight;  then  varnish  the  inside  with  shellac ; 
varnish  several  times ;  let  it  get  dry  and  hard ;  pour  in  three  gallons  of  water,  and  add 
nine  or  ten  pounds  of  common  washing  soda ;  when  dissolved,  add  one  quart  of  sawdust 
FIG  300  which  has  been  made  from  cutting  crossways  of  the  stuff,  as  this  is  more 
solid ;  the  sawdust  prevents  the  glass  from  lying  so  close  together,  and 
does  not  scratch,  and  gives  the  solution  a  chance  to  get  all  through 
between  them  all  the  time.  Twenty-four  hours  will  loosen  the  varnish, 
and  it  will  wash  clean  when  under  the  tap;  after  they  are  cleanly 
washed  place  them  carefully  one  by  one  in  strong  nitric  or  sulphuric 
acid ;  twelve  hours  after  this  wash  under  the  tap  with  a  good  stream 
of  water  running,  with  a  clean,  soft  sponge  that  has  no  grit  in  it;  after 
rinsing  the  plate  well,  then  draining  a  few  seconds,  it  is  ready  for  the 
albumen.  The  article  represented  by  Fig.  300  is  the  best  I  have  found 
amongst  many  ways  of  coating  the  plates.  No  bubbles  or  specks  will 
bother  you  when  properly  used.  There  is  a  funnel  on  top,  by  which 
you  filter  each  time  you  pour  from  your  plate,  and  is  of  such  a  shape  as  not  to  spill  out 
while  pouring. 

And  for  varnish  it  works  like  a  charm.  You  filter  all  the  dirt  out  through  the  cotton 
in  the  funnel;  this  is  tin,  3£  inches  diameter  on  bottom,  2£  inches  on  top,  with  a  lid  to 
which  the  runnel  is  fast.  The  height  is  five  inches. — E.  DOANE. 

142.  I  was  once  in  a  terrible  fog.  Friends  came  to  the  rescue,  and  suggested  many 
things,  such  as  examination  of  dark  slide,  camera,  and  dark-room  window  for  possible 
access  of  white  light;  the  examination  of  the  dark-room  walls  for  alkaline  emanations, 
fungoid  growths,  etc.  Everything  seemed  in  vain.  I  visited  a  friend's  studio  and  tried 
a  plate  with  his  chemicals ;  all  went  well.  I  took  a  stock  of  collodion,  bath,  and  devel- 
oper home  from  my  friend,  and  tried  them  in  my  own  dark-room  with  the  old  result — 


NEGATIVE-MAKING  —  WET.  30o 

Sometimes  the  fog  or  veil  which  covers  the  film  is  so  persistent  that  one  may 
neutralize,  sun,  boil,  acidify,  dilute,  strengthen,  add  permanganate  of  potash, 
and  what  not,  to  the  solution,  without  removing  it.  One  or  the  other  of  these 
treatments  should  correct  the  evil,  but  sometimes  there  are  local  causes  which 
prevent. 

When  such  trouble  comes,  sit  down  coolly  and  consult  Photographies.  It 
will  probably  show  you  a  way  to  overcome  the  nuisance. 

143.  Fog  to  the  photographer  is  as  baneful  as  a  sunless  sky  to  the  hay- 
fog.  Almost  hopeless,  I  felt  disposed  to  pull  my  dark-room  to  pieces.  I  proceeded  to 
strip  the  paper  off  the  walls,  in  doing  which  rather  hastily  underneath  the  sink,  through 
feeling  cramped,  and  not  being  at  the  time  in  the  pleasantest  mood,  I  damaged  (fortu- 
nately for  me)  the  gutta-percha  waste-pipe  from  the  sink;  finding  it  to  be  very  brittle 
through  long  use,  I  thought  it  would  be  much  better  to  have  a  new  one  than  to  waste 
time  in  trying  to  mend  it ;  so  I  got  a  chisel,  and  as  soon  as  I  had  chipped  the  mortar 
away  from  round  the  pipe  it  appeared  loose.  I  took  hold  of  it,  and  drew  it  out.  I  could 
see  at  once  there  was  not  sufficient  to  reach  through  a  double  brick  wall.  I  went  to  the 
outside  and  saw  the  pipe  still  in  the  wall ;  after  cutting  that  out,  I  found  in  the  centre  a 
quantity  of  wet  deposit.  This  had  been  confined  in  with  mortar,  inside  and  out,  for 
goodness  knows  how  long,  and  had  been  soaking  in  the  wall,  hence  the  fungoid  growth 
upon  it.  This  accumulation  of  hypo,  iron,  pyro,  acetic  acid,  etc.,  would,  I  think,  give 
off  a  quantity  of  sulphurous  gas  quite  sufficient  to  fog  any  plate.  At  all  events,  whether 
so  or  not,  I  am  most  thankful  to  say,  since  I  have  removed  that  and  put  a  new  pipe,  the 
wall  is  drying,  and  my  plates  have  been  clear  from  fog  every  day  since.  I  now  can  get 
a  very  fair  negative  from  my  large  bath,  with  which  before  every  plate  fogged  fearfully. 
I  feel  that  there  is  every  hope  now  that  the  cause  is  removed. — G.  W.  WALLACE. 

143.  It  is  a  mistaken  idea,  excess  of  iodide  in  a  bath.  I  claim  it  is  not  possible  when 
it  is  kept  up  to  the  original  or  proper  strength,  and  that  pinholes  from  excess  of  iodide 
are  only  the  surest  indication  of  weakness. — S.  M.  ROBINSON. 

"  Why  don't  you  add  water  first,  and  precipitate  the  iodide  ?  That 's  what  most  of 
the  authorities  recommend." 

Can't  do  it  Focus ;  never  did  it  in  my  life,  and  don't  believe  in  it.  More  operators  have 
been  led  into  difficulty  by  following  such  suggestions,  and  keeping  their  baths  insufficiently 
iodized,  than  have  ever  been  benefited  by  it.  When  I  make  up  my  bath,  after  boiling, 
to  the  proper  strength  and  bulk,  if  there  be  any  excess  of  iodide  it  will  filter  out  and 
leave  the  bath  with  just  the  quantity  it  needs,  saturation.  And  I  believe  it  will  receive 
no  more,  theories  to  the  contrary  notwithstanding ;  and  if  this  strength  be  kept  up,  it  will 
never  show  excess  of  iodide.  There  may  be  exceptions  to  this  in  warm  weather,  when 
the  bath  is  at  a  high  temperature  and  considerable  evaporation  takes  place.  In  that  case 
the  bulk  is  reduced  by  evaporation,  and  the  quantity  of  silver  by  use;  but  the  relative 
strength  remains  the  same,  as  well  as  the  original  quantity  of  iodide,  which  is  in  excess, 
not  from  any  additions  to  it  by  use,  but  from  the  very  reasonable  fact  that  there  are  not 
so  much  silver  and  water  as  in  the  first  place  to  hold  it. — ROLAND  VAN  WEIKE. 


304 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


maker.  Even  worse  is  it  when  his  films  present  the  appearance  of  a  map  of  a 
sectional  view  of  the  Pleiades — are  full  of  spots,  which,  in  photographic 
parlance,  are  termed  "  pinholes."  They  result  from  various  causes,  and  are 
met  in  a  variety  of  forms.  The  chief  cause  is  an  over-iodized  bath.  Such  a 
condition  occurs  after  considerable  use.  The  usual  remedy  is  to  filter  the  bath 
after  precipitation.  There  are  two  or  three  opinions  on  this  subject.  Some 
manipulators  find  a  day  or  two  of  exposure  to  the  sunshine  more  efficacious 
than  filtration.  The  evil  need  not  occur  in  the  hands  of  a  careful  and  exacting 
manipulator. 

All  these  annoyances  are  the  result  of  matter  in  the  wrong  place.  The  true 
remedy  is  to  find  out  what,  and  where,  is  the  matter. 

There  are  two  sides  to  most  questions,  and  there  are  two  to  this  ;  but  I  have  yet  to  hear 
a  reason  given  for  taking  iodide  from  the  bath  other  than  that  of  avoiding  pinholes,  which 
are  merely  nightmares  that  seldom  appear,  and  are  now  being  proved  not  to  be  caused  by 
an  excess  of  iodide ;  while  even  the  advocates  of  the  precipitation  theory  admit  that  the 
condition  of  the  bath  just  before  it  begins  to  show  pinholes  is  the  most  favorable  for 
producing  excellent  work.  This  then  is  the  important  point,  to  keep  it  as  near  as  pos- 
sible to  that  excellent  condition,  which  is  that  of  saturation  with  iodide  of  silver,  and 
the  maintenance  of  its  strength  at  as  uniform  a  standard  as  it  is  possible  to  secure. — 
E.  J.  CHUTE. 

I  have  found  the  following  an  excellent  treatment  for  the  negative  bath  overcharged 
with  iodides  and  weakened  by  the  quantity  of  alcohol  and  ether  dissolved  therein. 

Having  turned  the  bath  into  a  glass  jar,  at  least  large  enough  to  hold  twice  the  volume 
of  the  bath,  add  to  it  distilled  water  until  the  bath  is  reduced  to  15  or  20  grains  to  the 
ounce ;  it  will  assume  a  milky  color,  but  will  clear  up  by  being  allowed  to  stand  a  few  hours, 
after  which  filter  closely  into  an  evaporating  dish,  evaporate  slowly  over  a  water-bath 

until  it  is  only  about  one-eighth  its  original 
volume  (120  to  130  grains  to  the  ounce), 
remove,  cool,  and  add  distilled  water  until  it 
is  brought  to  the  standard  of  strength  de- 
sired. Let  it  stand  one  day  in  the  sunlight, 
when,  after  filtering  closely,  it  will  work 
charmingly,  and  pictures  will  not  easily  fog. 
I  send  you  a  sketch  of  a  contrivance  for 
a  still.  A  is  the  condenser  perforated  with 
water  flues ;  B,  the  tank  in  which  the  con- 
denser is  immersed;  C,  the  generator;  G, 
th.e  steam  pipe ;  D,  the  receiver  of  distilled 
water,  and  F,  the  supply  cistern  of  cold 

water,  which  should  be  so  placed  that  the  water  will  fall  upon  the  top  of  the  condenser ; 
E  is  the  hot  water  waste  taken  out  at  H. — F.  \V .  SPENCER. 


FIG.  301. 


NEGATIVE -MAKING — WET. 


305 


144.  Stains  and  "  marble"  marks  upon  the  negative  are  a  common  disorder. 
Their  causes  are  various — usually  a  scum  on  the  surface  of  the  bath  solution 
which  gathers  there  after  use.  A  few  drops 
of  water  in  the  collodion  will  often  temporize 
a  remedy.  Careful  attention  to  the  solution 

FIG.  302. 


FIG.  303. 


will  prevent  the  disease.  " Comets/7  "oyster 
shells/'  "volcanoes,"  and  " splurges"  are,  as  a 
rule,  the  result  of  carelessness  (Figs.  302, 303). 

144.  Dirty  fingers  are,  I  think,  the  most  likely  cause.  My  suspicion  will  appear  to 
have  some  weight  in  it  when  we  reflect  how  we  handle  the  extremely  sensitive  glass-plate. 
First,  many  of  us  hold  it  by  the  corner  to  collodionize  it ;  and,  if  one's  thumb  should  be 
warm  and  at  all  tainted,  away  goes  the  evil  into  the  bath,  and  must  act  in  various  ways 
to  injure  both  the  bath  and  plate.  But  the  next  operation  is  the  most  fertile  source  of 
these  marblings.  While  the  plate  is  in  the  bath  we  make  use  of  the  few  minutes  in 
wiping  our  slide,  seeing  that  our  developing  glass  is  clean  and  so  forth  ;  then,  often  with- 
out washing  our  hands,  we  re-enter  the  tent,  lift  up  the  plate,  and  seizing  one  corner 
hold  it  until  we  think  it  is  drained  sufficiently  for  the  slide.  Well,  now,  in  this  act  we 
place  our  thumb  and  finger  upon  a  vertical  moving  surface,  and  should  the  finger  be  in 
the  least  tainted,  what  can  be  more  natural  than  that  the  liquid  next  it  should  be  affected 
and  run  its  course  down  the  plate,  settling  in  various  parts,  according  to  the  moisture  of 
the  plate,  when  touched?  Besides,  we  often  finger  the  other  corners  while  adjusting  the 
plate  in  the  dark  slide,  and  so  cause  further  mischief. 

Most  of  us  have  found  that  these  stains  appear  and  disappear  when  no  change  has 
been  made  in  the  chemicals,  etc.,  and  occur  more  frequently  in  hot  weather,  which  facts 
favor  my  suspicions. 

If  dirty  or  new  carriers  are  frequently  the  cause  of  these  stains,  then  unclean  fingers 
must  be  offenders  also ;  but  we  can  prevent  this  evil  by  washing  our  hands  before  han- 
dling the  plate,  and  when  lifting  it  from  the  bath  keep  it  on  the  dipper  for  two  minutes, 
at  least,  before  touching  it.  I  have  often  thought  some  plan  might  be  found  for  suspen- 
ding the  dipper  and  plate  during  the  draining,  and  should  any  one  have  hit  upon  one, 

20 


306        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  real  fact  is  the  careful,  clearly  and  thoughtful  photographer  is  rarely 
troubled  with  the  annoyances  described.  And  thoughtfulness  is  about  as  good 
a  preventive  as  any. 

it  would  be  of  great  service  to  know  it.     Silver-wire  dippers  could  be  more  easily  man- 
aged than  glass  ones. — HENRY  PIPER. 

The  bath  should  be  always  perfectly  free  from  scum,  and  in  hot  weather  the  developer 
may  usefully  be  reduced  by  mixing  an  equal  quantity  of  water.  But  I  am  satisfied  that 
each  and  all  of  these  precautions  will  be  found  far  less  effective  than  that  to  which  I  have 
here  called  attention. 

Before  closing,  it  may  be  well  to  remark  that  few  photographers  are  aware  how  easily 
and  perfectly  these  stains  may,  for  the  most  part,  be  removed. 

This  is  best  done  before  the  negative  is  fixed.  Keeping  the  plate  very  wet,  take  a  very 
soft  gilder's  brush  (it  should  be  very  soft,  an  ordinary  camel's-hair  pencil  is  wholly  un- 
suitable), and  wetting  the  brush  also  thoroughly,  pass  it  over  gently  and  steadily.  The 
stain  will  at  first  resist,  but  presently  comes  away  as  a  white  powder.  It  will  cease  to  be 
visible  by  transmitted  light  some  time  before  it  disappears  by  reflected,  and  it  is  best  to 
stop  as  soon  as  the  first  of  these  results  is  effected.  On  one  occasion  I  had  a  negative  of 
which  near  one-third  of  the  surface  was  covered  by  these  stains ;  I  did  not  wish  to 
lose  it,  and,  with  a  little  care  succeeded  in  getting  rid  of  the  whole  of  them.  Without 
great  care  and  gentleness,  however,  the  film  will  give  way;  with  good  pyroxyline  and 
careful  manipulation,  however,  this  need  rarely  happen.  A  piece  of  extremely  soft  paper, 
thoroughly  wetted,  answers  even  better  than  the  gilder's  brush,  and  is  less  apt  to  break 
the  film.  The  paper  must  not  be  folded,  but  a  single  thickness  tapering  to  a  point  must 
be  well  wetted,  and  the  point  be  drawn  gently  over  the  stain. — M.  CAREY  LEA,  M.D. 

I  use  a  flat  well-bath  formed  of  porcelain,  the  well  at  the  end  of  the  tray  being  of  such 
capacity  as  to  hold  enough  liquid  to  flood  the  plate  thoroughly  when  placed  on  the  bot- 
tom of  the  tray,  and  an  inclined  motion  given 

FlQ-  304-  to  the  latter.     This  will  be  better  under- 

stood from  the  following  diagram  (Fig.  304), 
in  which  is  represented  the  bath,  the  end  a 
forming  the  well  of  which  we  have  spoken. 
The  open  space  of  the  bath  represents  the 
dimensions  of  the  largest  plate  capable  of 
being  sensitized,  and  a  ledge  upon  the  bottom, 
which  cannot  be  shown  in  the  diagram,  prevents  the  plate  from  slipping  down  into  the 
well  when  the  tray  is  tilted  upwards  in  the  manner  and  for  the  purpose  now  to  be  described. 
The  well-tray  is  fitted  into  a  wooden  case  constructed  in  such  a  manner  as  to  allow  a 
plate  to  lie  in  a  horizontal  position.    It  stands  on  two  end-pieces,  one  of  which  is  inclined 
inwards  at  a  considerable  angle,  the  object  of  which  is  to  allow  of  the  bath  being  reared 
up  on  one  end  in  a  sloping  direction.     The  diagram  (Fig,  304)  shows  the  configuration 
of  the  case  in  section.    The  solid  line  indicates  the  bath  in  outline,  while  the  dotted  line 
represents  the  case. 
The  use  of  the  apparatus  is  as  follows  :  The  well  having  been  nearly  filled  with  nitrate 


NEGATIVE-MAKING  —  WET.  307 

145.  Of  course,  constant  use  will  weaken  the  strength  of  the  nitrate  bath. 
Under  such  circumstances  it  becomes  very  human  and  acts  very  much  as  tired 

of  silver  solution,  and  the  bath  having  been  previously  placed  so  as  to  stand  at  a  slope, 
the  collodionized  plate  is  laid  upon  the  bottom,  its  lower  end  resting  upon  the  shallow 
ledge  of  which  we  have  spoken.  An  easily-fitting,  although  light-tight,  wooden  cover 
is  now  placed  upon  the  case,  and  the  bath  is  laid  in  a  horizontal  position,  by  which  the 
silver  solution  flows  over  the  plate  in  an  unbroken  sweep.  All  this  may  be  done  in  a 
lighted  room,  owing  to  the  exclusion  of  the  light  from  the  bath.  After  allowing  the 
plate  to  remain  immersed  for  any  determined  portion  of  time  the  bath  is  reared  up  on 
end,  by  which  the  liquid  flows  back  into  the  well,  leaving  the  plate  in  a  sloping  position 

to  drain. 

f 

It  has  already  been  shown  that  the  perfect  drainage  of  the  plate  in  a  moist  atmosphere 
is  an  effectual  preventive  of  the  formation  of  surface  markings,  and  it  will  be  seen  that 
the  bath  now  described  provides  the  requisite  conditions  for  effecting  the  necessary 
drainage.  The  interior  of  the  case  and  of  its  cover  is  coated  with  paraffine,  by  which 
both  remain  unaffected  by  the  moisture. — G.  W.  FOXLEE. 

145.  Let  us  consider  what  is  the  condition  of  a  bath  that  has  been  used  until  purifica- 
tion becomes  necessary,  as  compared  with  a  freshly  made  solution  in  good  working  order. 
The  old  bath  would  be:  (1)  overloaded  with  ether  and  alcohol;  (2)  diminished  in  bulk 
and  strength ;  and  (3)  it  would  contain  a  varying  proportion  of  injurious  substances 
called  "  organic  matter"  for  want  of  a  better  expression,  as  well  as  an  excess  of  iodide  of 
silver.  Plainly,  then,  any  method  of  purification  to  be  effective  must  be  one  that  will 
remove  the  ether,  alcohol,  organic  matter  and  iodides,  and  make  up  strength  and  bulk ; 
and  by  far  the  best  one  in  our  estimation  is  to  throw  down  the  silver  in  the  form  of 
carbonate,  and,  after  a  thorough  washing,  to  redissolve  it  with  nitric  acid.  The  fact  of 
the  silver  being  in  the  form  of  an  insoluble  precipitate,  capable  of  being  washed,  insures 
a  perfect  removal  of  the  ether  and  alcohol,  and,  although  it  may  be  possible  that  some 
of  the  iodides  are  taken  up  again  by  the  nitric  acid  after  being  thrown  down  with  the 
precipitate  of  carbonate  of  silver,  still  the  solution  will  be  found  not  to  give  any  sign 
whatever  of  their  presence,  nor  of  the  evils  which  follow.  The  organic  matter,  and 
probably  a  large  proportion  of  the  iodides  remain  behind  in  the  form  of  a  dirty,  black, 
and  insoluble  mud,  which  may  be  easily  filtered  out,  leaving  a  clear,  neutral  solution 
of  pure  nitrate  of  silver,  which  can  be  used  at  once  after  bringing  it  to  the  proper 
strength  by  the  hydrometer  and  acidifying  as  usual.  If  the  bulk  be  short,  the  proper 
amount  of  fresh  crystallized  silver  and  water  may  be  added. 

Boiling  a  bath  is  not  by  any  means  as  efficient  a  manner  of  purification  as  it  is  generally 
believed  to  be.  There  is  nothing  in  an  old  solution  coagulable  by  heat  alone,  so  that, 
unless  the  bath  was  thoroughly  sunned  after  being  neutralized,  the  organic  matters 
would  remain  after  the  boiling.  The  bath  should  be  diluted  previously  and  thoroughly 
filtered  before  the  boiling,  if  this  plan  must  be  followed.  Adding  fresh  silver  and  water 
before  boiling,  and  then  filtering,  is  a  most  erroneous  plan,  and  the  fact  of  the  solution 
working  well  after  this  messing  has  been  gone  through  with,  proves  nothing  one  way  or 
the  other.  It  is  absurd  to  put  fresh  silver  into  a  solution  already  foul  and  awaiting 


308         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

humanity  does  when  overworked.  The  remedy  is  obvious.  But  the  disease 
has  crept  in  slowly  and  therefore  the  cure  must  be  effected  gently. 

purification.  Neither  can  we  understand  what  is  meant  by  "  acid  being  present  in  a 
passive  condition."  This  is  carrying  things  too  far,  for  the  solution  must  be  either  acid, 
alkaline,  or  neutral,  and  the  question  of  what  chemical  function  is  performed  by  a  sub- 
stance not  capable  of  responding  to  any  known  test  may  be  very  properly  dismissed  from 
an  article  of  this  kind,  and,  at  all  events,  the  infinitesimal  quantity  of  a  new  compound 
formed  by  the  neutralization  of  a  bath  (either  with  acid  or  alkali)  might  be  disregarded. 
At  the  risk,  then,  of  being  somewhat  tedious,  let  us  repeat  that  if  a  bath  is  to  be  boiled, 
the  operations  should  follow  each  other  thus :  (1)  Neutralization,  preferably  with  bicar- 
bonate of  soda;  (2)  dilution,  thorough  sunning  and  filtering;  (3)  boiling  nearly  to 
dryness ;  (4)  making  up  to  the  proper  strength ;  (5)  filtering  and  acidifying. 

The  precipitation  method  is  carried  out  as  follows :  Provide  a  large,  strong  bottle  or 
jar  capable  of  holding  four  or  five  times  the  bulk  of  the  bath  to  be  purified.  Filter  the 
bath  into  this  jar  and  add  a  sufficient  quantity  of  a  filtered  saturated  solution  of  bicar- 
bonate of  soda  to  precipitate  the  silver.  It  will  require  quite  a  large  quantity  of  soda  to 
do  this,  and  as  there  is  violent  effervescence,  care  must  be  taken  not  to  add  too  much  at 
one  time,  and  to  shake  well  between  each  addition.  When  the  silver  is  all  down,  allow 
it  to  settle,  and  draw  off  the  supernatant  water  with  a  siphon  (a  yard  of  India-rubber 
tubing,  one  end  inserted  into  the  bottle  and  the  other  sucked  with  the  mouth  till  the 
fluid  flows,  answers  very  well).  Fill  up  the  bottle  with  water,  shake,  allow  to  subside, 
and  draw  off  as  before.  Repeat  this  half  a  dozen  times  or  more,  and  finally  add  nitric 
acid  very  cautiously  until  the  precipitate  is  not  quite  all  dissolved.  At  this  stage  of  the 
process  the  solution  will  look  black  and  muddy  ;  throw  it  on  a  filter  and  test  with  litmus 
paper ;  it  should  be  neutral.  Then  add  water  enough  to  make  the  strength  right,  and 
acidify. 

A  bath  so  treated  is  really  a  new  bath,  and  will  be  found  to  work  perfectly.  It  is  best 
to  conduct  the  whole  process  by  yellow  light,  and  it  is  presupposed  that  the  water  for  the 
washing  is  pure  and  soft,  or  at  least  the  same  kind  of  which  the  bath  is  to  be  made.  If 
the  water  is  hard,  the  last  three  washes  may  be  made  with  distilled  water  or  melted 
clean  ice.  Each  filtration  must  be  done  through  a  fresh  piece  of  paper.  Two  thick- 
nesses of  the  ordinary  gray  kind  may  be  used. — EDWARD  L.  WILSON. 

The  stubborn  bath  would  not  yield  until  cyanide  of  potassium  was  resorted  to.  The 
addition  of  it  brought  about  a  better  state  of  affairs.  A  little  of  a  fresh  solution  was 
added,  just  sufficient  to  cause  a  permanent  turbidity.  The  solution  was  then  placed  in 
the  feeble  light  of  a  winter  sun,  which  gleamed  out  fitfully  at  intervals  during  a  week. 
A  very  short  exposure  blackened  the  particles  of  cyanide  of  silver  in  suspension,  and 
finally  the  solution  became  perfectly  bright  and  clear,  having  deposited  a  copious  pre- 
cipitate, which  was  removed  by  filtration. 

The  bath  was  then  tried  without  any  addition  of  acid,  with  one  or  two  samples  of  good 
commercial  bromo-iodized  collodion,  and  the  result  was  surprising.  The  film,  on  removal 
from  the  bath,  presented  a  perfectly  even  creamy  coating,  free  from  marks  of  any  kind. 
On  applying  the  iron  developer  after  exposure,  the  image  came  out  with  remarkable 
vigor,  with  dense  lights  and  clean  transparent  shadows. — GEORGE  W.  WALLACE. 


NEGATIVE-MAKING  —  WET.  309 

146.  After  all  care,  reasonable  and  sometimes  unreasonable,  the  product  of  our 
manipulations  will  occasionally  finish  weak,  flat,  and  insipid  looking  without 
the  density  required  to  produce  first  class  prints.  Overexposure,  want  of  har- 
mony between  collodion  and  bath,  a  weak  bath  and  too  short  time  given  to 
sensitizing  the  film  are  among  the  leading  causes  of  weakness.  The  best  way 

146.  The  formula  I  give  is  for  a  portrait  or  landscape,  and  not  for  reproduction 
requiring  considerable  intensity: 

No.  1.  Bichloride  of  mercury,  £  ounce;  water,  20  ounces.  No.  2.  Water,  20  ounces; 
iodide  of  potassium,  20  grains.  No.  3.  Water,  4  ounces;  of  No.  1,  £  ounce. 

The  negative  is  taken,  washed  and  fixed,  and  washed  well  and  dried.  Then  flow  the 
negative  with  water,  and  flow  it  with  No.  3  just  long  enough  to  discolor  the  film,  and 
well  wash  and  flow  with  No.  2,  and  as  soon  as  the  dark  film  becomes  evenly  tinted  with 
the  solution,  wash  and  dry.  It  will  be  found  that  the  mercury  has  not  penetrated  through 
the  film,  but  only  just  acted  on  the  surface  to  which  it  was  applied.  On  looking  at  the 
back  of  the  negative  it  will  be  seen  as  before  the  mercury  was  applied,  but  the  surface 
will  show  the  creamy  effect  of  the  iodide  of  silver.  On  looking  through  the  negative,  it 
will  be  found  to  be  of  a  dirty  greenish-yellow  and  transparent,  and,  if  properly  done, 
will  be  found  to  give  a  soft,  brilliant  print,  and  the  negative  will  not  change  in  the  sun. 
I  find  many  use  a  solution  of  bichloride  of  mercury  and  iodide  of  potassium  mixed  in 
one  solution,  but  it  is  really  a  very  bad  intensifier  for  portrait  negatives,  and  the  negative 
will  change  in  the  light. — JEX  BARDWELL. 

There  are  certain  difficulties  connected  with  the  use  of  the  mercury  treatment,  as  an 
intensifier  after  fixing,  that  are  sometimes  so  annoying  as  to  cause  some  photographers 
to  abandon  it  entirely.  When  the  sublimate  solution  is  employed  only  till  it  blackens 
the  negative,  it  will  often  act  unequally.  If  the  negative  be  left  in  until  it  whitens,  with 
a  view  to  subsequently  treating  it  with  iodine  or  with  sulphide  of  potassium,  it  will 
sometimes  happen  that  the  picture  becomes  veiled.  That  which  before  immersing  in 
the  mercury  was  clear  glass,  may  come  out  with  a  thin  whitish  deposit.  If  now  the 
iodine  or  the  sulphide  be  applied,  this  whitish  deposit  becomes  black,  and  the  negative 
suffers  greatly. 

To  avoid  these  troubles,  I  proposed  the  following  mode  of  action  :  Leave  the  plate  in 
the  sublimate  solution  until  it  is  completely  and  evenly  white.  Wash  it  well  off,  and 
pour  over  it  a  solution  of  cyanide  of  potassium  of  one  grain  (or  not  exceeding  two  grains) 
to  the  ounce.  This  will  rapidly  blacken  the  negative  strongly,  at  the  same  time  clearing 
it  up.  It  must  be  poured  very  evenly  over  the  film,  or  used  as  a  bath,  and  must  be 
washed  off  as  soon  as  the  effect  is  produced,  for  if  allowed  to  continue,  it  will  whiten  the 
film  again. 

It  is  evident  that  this  process  is  particularly  suitable  to  copying  from  engravings.  It 
may  also  be  applied  where  the  picture,  by  mismanagement,  has  become  slightly  veiled 
during  development,  and  is  especially  useful  in  cases  where  mercury  has  been  applied, 
resulting  in  a  deposit  on  the  high  lights,  to  know  that  the  negative  is  not  thereby  spoiled, 
but  can  be  saved  by  using  cyanide  as  here  described,  instead  of  the  ordinary  treatment. 
— M.  CAREY  LEA,  M.D. 


310        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY, 

to  correct  the  evil  is  to  make  another  negative.  When  that  cannot  be  done 
resort  must  be  had  to  strengthening  or  intensification.  With  an  over  dense 
negative  but  little  can  be  done  except  to  throw  it  away. 

As  a  rule  intensification  is  not  recommended.  More  space  is  devoted  to  the 
subject  in  Wilson's  Photographies — more  methods  of  doing  it — more  reasons 
for  not  doing  it.  In  case  of  emergency  reference  can  be  had  thereto  and  thus 
more  space  left  here  for  greater  necessities. 

Thus  much  for  the  "wet"  method.  We  now  join  the  caravan  and  turn 
to  the  "dry." 

Perfect  Negatives  without  Retouching. — I  give  the  following  formula,  which,  in  my 
hands,  produces  negatives  that  need  little  or  no  retouching : 

Plain  collodion,  8  ounces ;  iodide  of  ammonium,  32  grains ;  iodide  of  sodium,  8  grains ; 
bromide  of  potassium,  8  grains ;  bromide  of  cadmium,  16  grains ;  neutral  bath,  40  grains 
to  the  ounce.  Developer — Stock  solution:  Water,  64  ounces;  sulph.  iron,  Bounces; 
Epsom  salts,  2  ounces ;  acetic  acid,  about  one-half  ounce  to  12  ounces  of  stock  solution.  - 
CHARLES  EVANS. 


CHAPTER    XV. 

NEGATIVE-MAKING — "  DRY." 

147.  If  this  work  was  intended  to  serve  as  a  history,  many  a  long  chapter 
could  be  filled  with  the  details  of  the  brave  crusades  made  against  the  wet  col- 
lodion negative  process  by  the  knights  of  the  camera  who  have  so  generously 
fought  for  our  mutual  freedom.  More  than  once,  at  the  expense  of  much  toil 
and  experiment,  a  new  ruler  has  been  raised  to  the  throne,  only  to  become 
unpopular  and  to  witness  a  return  to  the  old  rule,  which  continued  to  be  the 
favorite! 

Chloro-bromide  emulsion,  chloro-iodo-bromide,  collodio-bromide,  and  col- 
lodio-albumeu  emulsion,  were  among  those  which  promised  most  for  a  success- 
ful reign,  but  their  time  was  short. 

147.  The  following  is  the  mode  of  preparation  of  my  chloro-bromide  emulsion  : 

Collodion. — Ether,  20  fluid  ounces;  alcohol,  12  fluid  ounces;  pyroxyline,  162  grains; 
bromide  of  cadmium,  320  grains;  bromide  of  ammonium,  64  grains. 

Add  half  the  alcohol  to  all  the  ether,  and  shake  up  with  the  pyroxyline;  throw  the 
salts  into  a  flask  with  the  rest  of  the  alcohol,  and  heat  till  dissolved;  add  to  the  other 
portion,  shake  up  well,  and  place  in  a  warm,  light  place  for  three  weeks ;  it  will  be 
better  still  in  two  or  three  months. 

This  collodion  will  require  16  grains  to  the  ounce  of  nitrate  of  silver  to  sensitize  it.  I 
always  use  fused  nitrate. 

Having  measured  out  the  quantity  of  collodion  to  be  sensitized,  weigh  out  16  grains 
of  very  finely  powdered  nitrate  of  silver  to  each  ounce,  throw  it  into  a  test  tube  or  flask, 
and  pour  over  it  alcohol  of  sp.  gr.  0.820  in  the  proportion  of  1  drachm  to  each  8  grains  of 
nitrate;  boil  for  a  few  minutes,  and  the  nitrate  will  dissolve:  pour  it  now  in  successive 
portions  into  the  collodion,  shaking  up  well  after  each ;  shake  about  five  minutes  after 
the  last  portion  is  added,  and  every  few  times  thereafter. 

In  twenty-four  hours  after  sensitizing,  the  mixture  will  be  in  condition  to  use.  The 
filtering  is  best  done  by  putting  a  piece  of  soft  clean  sponge  in  the  neck  of  a  funnel  and 
cutting  a  small  circular  filter  of  close  woven  linen.  Before  filtering,  the  collodio-bromide 
mixture  should  rest  quiet  for  two  or  three  hours  after  its  last  shaking. 

I  use  as  a  preservative  the  following:  Cover  a  quarter  of  a  pound  of  good  litmus  with 
hot  water ;  set  a  basin  or  plate  over  the  bowl  and  put  in  a  warm  place  for  a  day ;  throw 
the  paste  upon  a  filter,  and  pour  on  hot  water  till  the  filtrate  amounts  to  a  quart  (the 

(811) 


312          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  bromo-gelatiDe  process  had  been  offered  for  some  time,  and,  gradually 
gaining  supporters,  at  last  ascended  the  throne.  It  has  apparently  come  to  stay. 
A  great  many  rebelled  against  it  at  first,  but  its  more  loyal  subjects  remained 
firm,  until  by  comparing  notes  and  giving  of  what  they  knew,  they  have  won 
almost  universal  fealty  to  a  process  which,  it  is  almost  unanimously  agreed,  is 
a  very  satisfactory  substitute  for  the  old  method. 

The  bath-holder  and  the  dipper  are  hung  upon  the  dark-room  wall  as 
trophies  of  past  battles,  with  no  less  affection  than  the  old-time  Crusader  felt 
when  he  hung  up  his  sword  and  shield. 

filtration  is  slow) ;  add  a  drachm  of  carbolic  acid  and  the  litmus  solution  keeps  good 
indefinitely:  Litmus  solution,  1  ounce;  water,  6  ounces;  gum  arabic,  90  grains;  sugar 
(fine  white),  90  grains;  acetic  acid,  No.  8,  25  minims. 

The  above  quantity  makes  a  convenient  bath  for  a  6 }  by  8  J  plate.  Throw  the  collodio- 
bromized  plate  into  a  pan  of  water  until  the  greasy  marks  are  gone,  and  then  pass  it 
into  this  bath,  where  it  should  remain,  with  occasional  agitation,  about  ten  minutes. 
The  time  is  not  important;  five  minutes  will  be  sufficient. 

The  tannin  preservative  is  as  follows:  Water,  7J  ounces;  gum  arabic,  90  grains;  sugar, 
90  grains ;  tannin,  15  grains.  The  washing  of  the  plate  is  the  same  as  above.  The 
development  may  proceed  by  the  strong  alkaline  development. — M.  CAREY  LEA,  M.D. 

In  my  chlor-iodo  bromide  process  we  have  silver  iodide  emulsified  with  bromide  and 
chloride,  and  in  some  hands  it  works  well.  The  collodion  is  made  thus:  Ether  0.730,  4 
drachms;  alcohol  0.805,  4  drachms;  pyroxyline,  8  grains.  To  every  ounce  of  collodion 
the  following  are  added:  Dried  cadmium  bromide,  9  grains;  ammonium  bromide,  2£ 
grains;  ammonium  iodide,  2  grains.  Directly  before  emulsifying,  add  aqua  regia,  2 
drops. 

The  emulsion  with  an  excess  of  silver  is  formed  by  adding  25  to  30  grains  of  silver 
nitrate,  and,  after  an  hour's  interval,  2  grains  of  cupric  chloride  or  cobaltic  chloride;  2 
drops  of  hydrochloric  acid  may  be  substituted  for  either  of  these  or  for  the  aqua  regia. 

The  emulsion  may  at  first  appear  flaky,  but  after  the  addition  of  the  chloride  it  is 
only  necessary  to  shake  well  and  leave  it  for  twelve  hours.  On  again  shaking,  the 
emulsion  will  be  found  perfect.  It  may  be  used  before  drying  or  after  drying.  In  the 
former  case  any  of  the  preservatives  ordinarily  used  may  be  employed. 

If  it  has  to  be  dried,  it  is  poured  out  into  a  dish  and  left  till  it  is  in  a  leathery  condi- 
tion on  the  surface,  after  which  a  preservative  is  poured  upon  it.  Any  preservative  will 
answer.  I  use  water,  6  ounces;  acetic  acid,  3  drachms;  solution  of  gum  arabic  with 
sugar,  4  drachms;  prepared  albumen,  1  ounce;  gallic  acid  (60  grains  to  1  ounce  of  alco- 
hol), 4  drachms ;  tannin  (60  grains  in  1  ounce  of  water),  2  drachms. 

The  albumen  is  prepared  by  the  addition  of  an  equal  bulk  of  water  to  the  white  of 
one  egg,  and  clarifying  with  twelve  drops  of  acetic  acid. 

The  gum  and  sugar  solution  is  made  by  mixing  half  a  pound  of  gum  arabic  and  two 
ounces  of  sugar  in  forty-four  ounces  of  water  and  adding  one  and  a  half  drachms  of 
carbolic  acid. 


NEGATIVE-MAKING — DRY.  313 

All  plate  rubbing,  collodion  flowing,  sensitizing  and  so  on,  are  done  away 
with.  The  sensitized  plates  are  received  from  the  manufacturer  ready  for  ex- 
posure in  the  camera.  Or,  if  the  manipulator  prefers  it,  he  may  prepare  an 
emulsion,  coat  his  glass  plates  with  it,  and  set  them  aside  for  use  whenever  it 
agrees  with  his  inclination,  be  it  weeks  or  months  or  years. 

Moreover,  he  can  expose  them  to-day  and  develop  them  a  year  hence,  should 
it  suit  his  convenience.  Again,  the  greatest  latitude  in  the  matters  of  exposure 
and  development  are  possible,  and,  when  touring  it  there  is  freedom  from  great 
weight  of  apparatus  and  appliances. 

The  pellicular  mass  is  then  broken  up,  and  it  and  the  preservative  are  transferred  to 
a  large  glass  jar,  and  left  there  twenty  minutes.  The  preservative  is  then  poured  off, 
and  the  washing  takes  place. 

Instead  of  drying  the  emulsion,  it  may  be  poured  direct  into  the  preservative,  taking 
care  that  the  latter  is  more  than  four  times  the  bulk  of  the  former.  The  washing  in 
this  case  takes  place  by  decantation  in  the  usual  manner.  This  last  method  is  stated  to 
give  the  most  soluble  pellicle.  The  pellicle  is  then  dried  in  the  oven  or  water  bath  and 
is  reemulsified  by  taking  for  each  three  ounces  of  the  original  collodion :  Ether,  1  ounce ; 
alcohol,  1  ounce;  plain  collodion  (4  grains  of  pyroxyline  to  the  ounce),  2  ounces. 

Shake  well  at  intervals,  and  in  a  week  it  is  ready  for  use.  The  plate  is  coated  in  the 
ordinary  manner  and  dried.  The*  exposure  is  about  equal  to  that  of  a  wet  plate. — M. 
CAREY  LEA,  M.D. 

The  collodio-albumen  process  is  as  follows.  Preliminary  coating:  Albumen  (the 
white  of  one  egg),  30  c.  c.  (8  fl.  drs.) ;  water,  70  c.  c.  (19  fl.  drs.) ;  ammonia,  1  to  2  c.  c.  (^ 
to  J  fl.  drs.)  Reduced  to  a  state  of  froth,  and  after  repose,  filtered  through  paper. 

After  complete  desiccation,  the  albumenized  plates  are  placed  in  a  grooved  box,  to  be 
used  when  wanted. 

The  collodionizing  of  these  albumenized  plates  is  done  preferably  with  old  collodion, 
or  with  a  mixture  of  two-thirds  new  collodion  and  one-third  of  old. 

Sensitizing  is  done  in  the  following  silver  bath:  Water,  100  c.  c.  (3£  fl.ozs.);  nitrate 
of  silver,  8  grammes  (123  grs.);  acetate  of  lead,  1  gramme  (15  grs.);  crystallized  acetic 
acid,  a  few  drops. 

It  is  very  advantageous  to  expose  the  sensitizing  bath  to  full  light  for  some  time,  and 
to  filter  before  using  it;  thus  are  avoided  the  fogs  and  reductions  which  may  occur  in 
the  development,  a  very  frequent  cause  of  failure  in  sensitized  dry  plates. 

After  sensitizing,  which  requires  about  three  minutes,  wash,  first  in  water  slightly 
acidified  with  acetic  acid;  then  cover  the  sensitized  coating,  1,  with  a  solution  of  phos- 
phate of  soda  at  three  per  cent.;  2,  of  gallic  acid  at  one  per  cent.,  and  without  washing, 
with  the  following  preserving  varnish:  Water,  100  c.  c.  (3£  fl.  ozs.);  pure  dextrin,  9 
grammes  (139  grs.);  gum  arabic,  1  gramme  (15  grs.).  Made  with  the  application  of 
heat,  and  after  the  addition  of  a  few  drops  of  acetic  acid  filtered  through  paper. 

The  plates  thus  prepared  are  placed  on  the  dryer,  so  as  to  obtain  a  regular  and  com- 
plete desiccation ;  they  will  preserve  their  quality  for  at  least  a  fortnight. 


314        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

148.  While,  as  a  rule,  it  will  be  found  most  certain,  and  certainly  the  most 
economical,  for  the  photographer  to  purchase  his  sensitive  emulsion  plates 
ready  made,  he  may  not  always  wish  to  do  so.  Therefore,  complete  formulae 
for  making  emulsions  of  various  kinds  will  follow,  with  all  the  notes  of  prac- 
tical worth  which  have  been  given  as  bearing  upon  the  subject. 

There  are  so  many  methods  that  manufacturers  of  plates  make  a  choice, 
fancying  that  they  see  advantages  in  one  which  are  not  possessed  by  others. 
This  causes  uncertainty  always  as  to  the  sensitiveness,  and  makes  it  necessary 
for  the  user  to  make  a  change  in  his  exposure  and  development,  as  well  as 
after-treatment,  every  time  the  brand  of  plates  is  changed. 

Development  of  the  Image. — The  exposed  plate  is  first  plunged  into  very  pure  water, 
then  into  another  dish  containing  tepid  water;  it  is  washed  for  the  last  time,  and  then 
exposed  to  the  following  reducer:  Water,  250  c.  c.  (8J  fl.  ozs.) ;  gallic  acid,  1  gramme  (15 
grs.);  pyrogallic  acid,  0.3  gr.  (4£  grs.);  acetic  acid,  3  c.  c.  (f  fl.  drs.);  alcohol,  3  cc.  (f 
fl.  drs.) ;  in  which  are  placed,  at  the  moment  of  the  immersion  of  the  plate,  a  few  drops 
of  a  solution  of  phosphate  of  soda  at  three  per  cent.,  and  a  few  drops  of  acetate  of  lead  of 
the  same  strength,  to  which  has  been  added  a  little  acetic  acid.  After  a  few  minutes  the 
plate  is  withdrawn,  and  a  trace  of  solution  of  silver  at  three  per  cent,  is  added.  The 
plate  replaced  in  this  energetic  reducer  soon  shows  all  its  details,  and  then  additional 
nitrate  of  silver  is  added  so  as  to  obtain  the  necessary  vigor. — ERNEST  BOIVIN. 

148.  The  relative  sensitiveness  of  dry  plates,  compared  with  the  wet,  is  not  constant,  but 
varies  with  the  amount  of  light — i.  e.,  the  stronger  the  light,  the  more  sensitive  the  dry 
plate,  compared  with  collodion,  and  the  weaker  the  light  and  the  longer  the  exposure 
required,  the  smaller  is  the  relative  sensitiveness  of  the  former. 

Take,  for  instance,  a  very  sensitive  dry  plate,  with  which  a  good  instantaneous  view, 
under  favorable  conditions,  can  be  made  in  from  one-fortieth  to  one-fiftieth  part  of  a 
second.  To  obtain  an  approximately  equal  result  with  a  good  collodion  plate  would 
require  at  least  two  or  three  seconds,  so  that  in  this  case  the  dry  plate  would  prove  from 
one  hundred  to  one  hundred  and  fifty  times  as  rapid  as  the  Wet.  Now,  with  the  very 
same  plates,  make  a  portrait  under  the  skylight ;  here  the  dry  plate  will  require  say  two 
seconds,  while  the  wet,  under  the  same  conditions,  will  have  to  be  exposed  sixteen  to 
eighteen  seconds,  so  that  the  former  will  this  time  prove  eight  or  nine  times  as  quick. 
In  a  very  dark  wood,  or  for  an  interior,  the  difference  of  the  two  plates  will  be  a  still 
smaller  one,  and  the  dry  plate  will  here  only  prove  three  or  four  times  as  rapid  as  the 
wet.  How  ought  one  to  mark  this  very  sensitive  dry  plate?  One  hundred,  nine,  or 
three  times  as  rapid  as  a  wet  plate? 

This  also  explains  the  contradictory  results  above  mentioned.  Some  manufacturers 
test  their  plates  for  an  out-door  view,  others  under  the  skylight ;  some  use  very  powerful, 
others  less  powerful,  lenses;  some  use  large,  others  small,  diaphragms;  and  they  will, 
therefore,  in  one  place  find  their  plates  thirty  times,  in  the  other  about  eight  or  ten  times 
as  quick  as  collodion. 


NEGATIVE- MA  KING  —  DRY. 


315 


Of  course,  it  would  be  too  much  to  expect  a  uniform  standard  of  plates. 
The  best  plan  is  to  choose  a  brand  from  which  you  can  produce  the  best  results, 
and  adhere  to  it.  Another  good  idea  is,  when  you  desire  a  quantity  of  plates, 
to  test  samples  made  from  certain  batches  of  emulsion,  find  which  suits  best, 
and  then  have  your  stock  order  made  from  that  emulsion. 

Since  a  number  is  given  by  the  dry-plate  manufacturer  to  each  emulsion  he 
mixes,  the  plan  suggested  is  not  a  difficult  one. 

149.  The  manufacture  of  emulsion  must  be  conducted  in  the  dark-room. 

The  reason  why  the  sensitiveness  of  the  dry  plate  increases  with  the  amount  of  light, 
respectively  with  the  shortness  of  exposure,  one  cannot  tell  with  certainty. 

Some  readers  will  perhaps  ask  here :  "  How  ought  one  to  mark  the  dry  plates,  so  that 
everyone  can  have  an  approximate  idea  of  their  sensitiveness,  and  guess  close  to  the 
right  time  of  exposure,  even  if  he  never  worked  the  brand  of  plates  before  ?" 

The  best  means  for  testing  and  determining  the  relative  sensitiveness  of  dry  plates,  up 
to  the  present  time,  is  by  a  sensitometer,  either  Vogel's  or  Warnerke's ;  and  I  would  advo- 
cate that  every  dry-plate  maker  should  test  his  plates  with  one  of  these  instruments,  and 
mark  the  packages  accordingly.  I  am  well  aware  that  these  instruments  have  many 
pros  and  contras,  which  to  discuss  here  would  lead  too  far ;  but  as  long  as  we  have  no 
better  means,  they  should  most  decidedly  be  used.  But  marking  sensitometer  degrees 
by  the  manufacturers  alone  will  be  of  very  little  use  if  the  customers  are  not  acquainted 
with  these  instruments,  and  know  what,  for  instance,  "  15  or  20  Warnerke  "  means.  If 
not  practically,  they  ought  at  least  theoretically,  be  acquainted  with  the  sensitometers. 
Our  photographic  journals  will  have  to  explain  these  instruments,  and  everyone  ought 
to  read  these  journals,  and  profit  by  them.— DK.  S.  C.  PASSAVANT. 

149.  The  following  apparatus  goes  far  to  lighten  the  labors  of  those  who  make  their 
own  gelatine  plates.  It  is  my  cooking-box,  warming-box,  etc.  (Fig.  305.)  1,  can  for 
warm  water ;  2,  lamp  for  heating. 

FIG.  305.  FIG.  306. 


J 


The  heat  from  lamp  passes  all  around  the  inside  can  containing  water.    Place  a  wire 
net  in  the  bottom  of  the  can  to  raise  the  jar  about  one  inch;  the  heat  will  then  be  even. 


316 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  307. 


FIG.  308. 


The  purest  and  best  ingredients  should  be  used,  and  cleanliness  and  exactitude 
cared  for  throughout. 

I  always  prepare  the  emulsion  the  evening  before  using,  and  place  to  filter  in  my 
warming-box,  made  as  design.  (Fig.  306.)  1,  warm-water  shield  for  funnel  containing 
filter. 

"  Pour  the  emulsion  in,  and  allow  it  to  drip  in  the  bottle  contained  in  warm-water 
can,  No.  2.  Place  a  small  lamp  in  at  No.  3,  and  keep  it  burning  so  that  the  heat  is  kept 
at  100°  till  after  the  flow  is  ended.  This  I  do  with  my  flowing  apparatus,  which  connects 
with  the  emulsion  bottle  by  means  of  a  small  rubber  hose  passing  in  the  heating-box 
through  the  hole  in  the  side  at  No.  4." — S.  L.  PLATT. 

For  the  preparation  of  gelatine  emulsion  a  water-bath  is  indispensable.  I  make  use 
of  an  ordinary  tea-kettle  when  experimenting  on  a  small  scale.  (Fig.  307.)  T  is  the  kettle 

filled  with  water  and  heated  by  the  Bunsen 
burner  B.  P  is  a  porcelain  jar  such  as  apotheca- 
ries use  for  medicines.  J  is  a  funnel  having  its 
neck  stuffed  with  cotton,  so  that  hot  water  (with 
which  it  is  first  filled) 
drops  into  the  jar  at  the 
rate  of  three  or  four  drops 
per  second.  S  a  glass  rod 
for  stirring,  t  a  thermom- 
eter. I  prefer  porcelain 
jars  rather  than  glass 
flasks  or  vessels  as  gener- 
ally recommended,  they 
are  not  so  likely  to  break. 
For  7  ounces  of  emul- 
sion then,  let  ajar  holding 
14  ounces  be  selected,  and 
about  twice  as  deep  as  it  is  broad.  If  gas  is  not  to  be  had,  a  powerful  Berzelius  lamp 
petroleum  cooking-stove,  or  charcoal  fire  with  bellows  and  good  draft  may  be  substituted. 
It  need  scarcely  be  said  that  the  apparatus  must  stand  in  the  dark-room.  For  illumina- 
tion a  lamp  with  ruby-red  chimney  may  be  used.  During  the  addition  of  the  silver,  and,  in 
fact,  as  long  as  there  is  an  excess  of  bromide  present,  it  is  not  necessary  to  be  over-cautious  about 
the  light,  for  the  bromide  keeps  down  the  sensitiveness  considerably ;  but  when  the  per- 
fectly washed,  highly  sensitive  emulsion  is  to  be  handled,  then  care  is  necessary,  and 
the  direct  light  of  the  lamp  should  not  be  allowed  access  to  it  longer  than  is  absolutely 
necessary.  At  the  distance  of  three  feet,  a  few  minutes  will  do  no  harm.  The  ceiling  of 
the  room  should  be  painted  black  in  order  to  prevent  reflection  from  the  lamp  (Fig.  308). 
In  this  manner  I  have  made  as  much  as  two  quarts  of  emulsion.  If  larger  quantities 
are  to  be  prepared,  I  advise  a  hollow  tin  case  to  be  adapted  around  the  funnel  and  filled 
with  the  water ;  this  will  keep  the  solution  warm.  Of  course,  larger  water-baths  will  be 
required. — DR.  H.  W.  VOGEL. 


NEGATIVE    MAKING  —  DRY.  317 

It  will  be  understood  that  the  temperature  at  which  the  gelatine  is  cooked, 
rules  the  degree  of  sensitiveness  of  the  resulting  emulsion — the  higher  the  tem- 

To  secure  gradations  of  higher  lights,  in  the  tone,  and  relief  in  the  shadows,  I  take 
three  beaker  glasses ;  in  the  first  I  put  370  grains  bromide  of  potassium,  4  gr.  iodide  of 
potassium,  310  gr.  best  gelatine,  7  fluid  oz.  distilled  water,  and  3-4  minims  glacial  acetic 
acid,  or  1^  gr.  of  citric  acid.  In  the  second  glass  I  put  460  gr.  crystallized  nitrate  of 
silver,  in  3J  fl.  oz.  of  distilled  water.  In  the  third  glass  I  dissolve  310  gr.  of  the  best 
gelatine  (216  gr.  hard  and  94  gr.  soft  for  warm  weather,  and  155  gr.  of  each  in  winter), 
in  8J  fl.  oz.  of  distilled  water. 

While  the  chemicals  are  dissolving,  and  the  gelatine  swelling,  I  get  ready  the  water- 
bath.  When  the  bath  is  hot,  I  put  in  the  contents  of  the  first  glass,  which  is  subjected  to 
successive  degrees  of  heat  until  the  gelatine  is  perfectly  dissolved.  The  solution  is  then 
transferred  to  a  black  bottle,  similar  to  those  employed  in  transporting  mineral  waters, 
and  stopped  with  a  cork,  cut  in  such  a  manner  as  to  afford  ventilation  to  the  bottle.  To 
the  contents  of  this  bottle  If  fl.  oz.  of  distilled  water  are  added,  and  well  shaken  ;  then 
the  solution  of  silver  nitrate  (second  bottle),  in  portions,  ten  in  all,  and  the  whole  again 
well  shaken  after  the  addition  of  each  portion.  The  bottle  and  its  contents  are  again 
transferred  to  the  bath,  and  suffered  to  digest  for  two  hours  at  150°  to  160°  F.  After 
this  digestion,  the  emulsion  is  quickly  cooled  down  to  85°  F.  During  this  time,  the 
gelatine  is  allowed  to  dissolve  in  the  third  glass,  and  the  solution  cooled  down  to  a  point 
at  which  it  remains  firm,  but  still  in  a  fluid  condition.  About  2  drachms  of  pure 
ammonia  are  now  added,  the  whole  well  shaken,  and  poured  into  the"  bromide  of  silver 
gelatine  emulsion,  which  has  been  cooled  down  to  85°  F.,  again  shaken,  and  immediately 
filtered,  without  further  digestion,  through  flannel  into  a  porcelain  dish,  and  left  to  set. 
After  the  setting,  the  gelatine  is  pressed  through  canvas,  and  washed  for  five  or  seven 
hours  in  running  water,  then  remelted  and  refiltered.  The  emulsion  is  now  in  readiness 
to  be  poured  upon  the  plates.  It  flows  and  dries  easily,  since  it  contains  comparatively 
little  water. 

I  prefer  the  oxalate  of  iron  developer,  without  the  preparatory  alum  bath,  or  addition 
of  bromide  of  potassium,  or  hyposulphite  of  sodium 

The  plates  are  very  sensitive,  and  give  brilliant  negatives,  with  rich  shadows,  free  from 
all  spots. — FRANZ  KNIEBEL. 

To  render  emulsion  films  insoluble  take  water  12  ounces,  alcohol  6  ounces,  chrome 
alum  12  grains. 

After  exposure  I  immerse  the  trial  plates  in  this  solution  for  two  or  three  minutes, 
perhaps  a  little  longer,  and  then  soak  them  in  a  dish  of  water,  using  a  camel's-hair  brush 
to  rid  them  of  the  bubbles  formed  by  the  alcohol  in  the  film  coming  in  contact  with 
water,  until  the  water  flows  smoothly  over  the  plate.  (It  would  also  be  well  in  all  cases 
to  use  the  brush  in  developing  to  insure  the  absence  of  bubbles.)  I  then  develop  them, 
and  they  come  up  clear  and  brilliant,  perhaps  a  little  more  brilliant  than  when  not  using 
the  alum ;  and  wash  them  in  water  of  about  100°  (warmer  than  it  is  likely  ever  to  be 
used  in  summer),  fix  as  usual,  and  wash  again  in  warm  water  as  before,  and  dry  sponta- 
neously. Not  a  particle  of  frilling  or  reticulation.  No  alum  was  used  except  that  men- 


318         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

perature  the  more  sensitive  the  emulsion.  Sensitiveness  is  also  secured  by  the 
addition  of  ammonia  to  the  bromide  of  silver. 

tioned  at  first.  A  longer  soaking  would  undoubtedly  cause  the  plate  to  stand  even  drying 
by  heat,  which  I  did  not  attempt,  as  I  don't  consider  it  essential. — D.  BACHRACH,  Jr. 

Slow  Emulsion/or  Landscape  Work. — I  will  give  a  formula,  although  I  claim  no  par- 
ticular merit  for  it,  except  that  I  have  tried  so  to  adjust  the  details  that  the  process  may 
be  as  simple  as  possible,  and  that  the  chance  of  failure  may  be  reduced  to  the  minimum : 
A.  Nitrate  of  silver,  200  grains ;  distilled  water,  3  ounces.  B.  Bromide  of  potassium, 
160  grains ;  iodide  of  potassium,  10  grains;  Nelson's  No.  1  gelatine,  40  grains;  muriatic 
acid,  2  £  minims;  water,  3  ounces.  C.  Hard  gelatine,  150  grains.  D.  Hard  gelatine, 
150  grains. 

The  gelatine  of  B  is  allowed  to  soften.  At  the  same  time  water  may  be  poured  over 
the  lots  of  gelatine  C  and  D  (kept  separate  one  from  the  other)  to  let  them  swell. 

A  and  B  are  now  heated  to  120°  F.,  and  A  is  poured  into  B  slowly,  with  vigorous 
stirring.  The  emulsion  thus  formed  is  allowed  to  stand  for  ten  minutes  with  occasional 
stirring.  Meantime,  as  much  of  the  water  is  squeezed  out  of  the  gelatine  C  as  is  pos- 
sible, by  wrapping  it  in  a  towel,  or  similar  piece  of  cloth,  and  wringing  the  cloth  round. 

After  ten  minutes  the  emulsion  (having  been  allowed  to  remain  without  stirring  for  at 
least  two  minutes,  to  allow  any  granular  bromide  which  may  have  been  formed,  to  sub- 
side) is  poured  over  C,  heat  being,  if  necessary,  applied  to  melt  the  gelatine.  When  the 
gelatine  and  the  emulsion  are  thoroughly  incorporated,  the  jar  containing  them  is  set  on 
one  side  to  allow-the  whole  to  set  into  a  stiff  jelly.  In  cold  weather  there  is  no  difficulty 
in  getting  the  emulsion  to  set,  but  if  the  weather  be  warm  it  should  be  allowed  to  stand 
in  a  vessel  containing  water,  with  a  lump  or  two  of  ice  in  it.  Once  thoroughly  set,  the 
emulsion  is  washed  in  any  of  the  well-known  ways,  being  either  squeezed  through  canvas, 
or  otherwise  cut  into  small  fragments.  When  it  has  been  washed  thoroughly  and  drained 
until  no  more  water  will  run  from  it,  JD  (having  had  as  much  water  as  possible  wrung 
out  of  it)  is  added.  The  whole  is  melted  up,  and  one-half  ounce  of  pure  alcohol  is  added, 
when  it  is  ready  for  coating  plates. 

The  quantity  of  emulsion  that  I  have  described  should  serve  to  coat  a  dozen  8  x  10 
plates.  A  skilled  coater  could  make  it  cover  a  dozen  10x12  plates  without  any  part 
being  too  thin. — W.  K.  BURTON. 

All  the  articles  employed  must  be  scrupulously  clean  and  dry.  Any  contamination 
by  dirt  of  any  description,  and  particularly  that  to  be  found  in  a  photographer's  work- 
room, is  almost  sure  to  spoil  the  emulsion,  or,  at  all  events,  its  sensitiveness,  and  to  cause 
endless  evils.  Hence  dean  paper  should  be  used,  and  the  chemicals  should  not  be  left 
on  the  benches  or  table  in  contact  with  the  wood.  The  scales  in  which  the  weighing  has 
to  take  place  should  be  examined  for  dirt  (chemical  or  otherwise)  and  a  few  circular  filter 
papers  on  which  to  weigh  the  materials,  should  be  at  hand.  Weighing  should  never  be 
done  without  a  filter  paper  of  equal  size  and  weight  being  placed  in  each  pan  of  the  scale. 
A  saucepan  of  hot  water  should  be  ready  in  which  to  place  the  beakers,  etc.,  in  which 
the  different  materials  have  to  be  dissolved,  and  care  should  be  taken  that  it  is  not  too 
full.  It  need  scarcely  be  said  that  all  weighing  can  be  done  in  ordinary  light.  To  com- 


NEGATIVE- MA  KING  —  DRY. 


Three  methods  will  be  given  for  the  preparation  of  emulsion,  therefore,  in- 
cluding one,  in  the  practice  of  which,  the  slow  boiling  of  the  gelatine  is  followed. 

mence  operations,  the  following  may  be  weighed  out  separately  and  placed  on  clean  paper 
after  weighing,  it  being  supposed  that  a  dozen  or  a  few  more  whole  plates  are  required : 
1.  Potassium  iodide,  10  grains ;  2.  Ammonium  bromide,  140  grains ;  3.  Nelson's  No.  1 
photographic  gelatine,  30  grains ;  4.  Silver  nitrate,  200  grains ;  5.  Nelson's  No.  1  photo- 
graphic gelatine,  80  grains ;  6.  Simeon's  Swiss  gelatine,  or  Coignet's  special  gelatine,  80 
grains.  Nos.  3,  5,  and  6  are  rapidly  covered  with  water,  shaken  or  stirred  in  it  a  few  sec- 
onds, and  the  water  poured  off  as  quickly  as  possible.  This  gets  rid  of  any  adherent 
dust  on  them.  Nos.  1  and  2  are  then  dissolved  in  1  drachm  and  1 J  ounces  of  water  (ordi- 
nary tap  water  is  good  enough)  respectively,  and  then  No.  3  is  added  to  No.  2  and  allowed 
to  swell  in  the  liquid.  It  may  require  a  little  coaxing  to  get  it  beneath  the  surface  of 
the  water,  but  if  a  good-sized  developing  cup  be  used  there  will  not  be  much  difficulty. 
When  swollen,  the  cup  containing  the  salts  and  the  gelatine  is  placed  in  boiling  water 
for  a  few  minutes,  till  the  latter  is  dissolved  (which  it  will  readily  do  in  a  very  short  time), 
and  raised  to  the  temperature  of  about  150°  F. ;  if  the  gelatine  be  alkaline,  1  drop  of 
hydrochloric  acid  may  be  added.  The  silver,  No.  4,  meanwhile,  is  also  dissolved  in  1? 
ounces  of  water,  slightly  warm. 

This  last  may  be  placed  in  a  spray  apparatus,  which  is  made  as  follows ;  Bend  two  thin 
glass  tubes  in  a  common  fish-tail  burner  of  the  shapes  A  and  A  (Fig.  309).  The  tube  A 
should  first  of  all  be  drawn  out  so  that  the  end  is  per- 
fectly closed ;  this  may  be  done  by  the  heat  of  a  Bun- 
sen  burner,  by  holding  the  straight  tube  over  it  at 
about  an  inch  from  the  end  in  one  hand,  and  at  any 
convenient  distance  in  the  other,  and  when  thor: 
oughly  softened  by  the  heat  at  one  point,  by  simply 
pulling  the  tube  outwards  the  glass  collapses,  and  the 
short  bit  is  pulled  off.  A  flat  file  is  then  applied  to 
the  point,  and  the  glass  filed  away  till  a  very  small 
orifice  is  left.  The  two  tubes  are  then  inserted  in  a 
cork  which  is  fitted  into  a  testrtube,  as  shown.  The 
silver  nitrate  is  placed  in  the  bottom  of  the  tube, 
and  a  very  fine  spray  of  liquid  can  be  forced  through 
the  orifice  of  A. 

The  solution  of  gelatine  and  bromide  should  be  placed  in  a  glass  beaker  or  a  jam  pot, 
and  in  the  dark-room  the  spray  is  blown  on  to  it,  and  the  liquid  stirred  at  the  same  time 
with  a  clean  glass  rod.  When  the  silver  nitrate  has  been  added  to  the  bromide,  the 
iodide  is  dropped  in  with  stirring,  and  the  remainder  of  the  silver  solution  subsequently 
added.  This  is  a  better  plan  than  adding  it  to  the  bromide  at  first,  and  depends  for  its 
value  on  the  fact  that  the  iodine  from  the  iodide  will  replace  the  bromine  from  the  silver 
bromide,  soluble  bromide  being  reformed ;  grains  of  silver  iodide  thus  formed,  have  the 
same  size  as  the  bromide  originally  formed.  This  gives  a  very  fine  emulsion  indeed,  and, 
if  correctly  carried  out,  a  drop  of  it  when  poured  on  a  strip  of  glass  should  show  an 


Fro.  309 


320 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


The  preparation  of  the  glass  is  substantially  the  same  as  that  given  for  the 
"wet"  process,  cleanliness  being  the  great  desideratum. 

orange-yellow  color  by  transmitted  daylight,  or  a  deep  ruby  when  a  gas  or  candle-flame 
is  examined  through  it.  The  possible  sensitiveness  of  an  emulsion  depends  almost 
entirely  on  the  fineness  of  grain  of  the  bromide  when  first  formed.  With  a  gray  or  blue 
tinted  emulsion,  extreme  rapidity  can  never  be  hoped  to  be  attained.  The  emulsion 
should  be  transferred  to  a  20-ounce  bottle,  and  well  shaken  for  a  couple  of  minutes,  after 
which  it  is  ready  for  the  next  operation. — C  4.PT.  ABNEY. 

If  two  one-drachm  measures  be  filled,  one  with  the  bromide  solution  and  the  other  with 
the  silver  nitrate  solution,  and  then  be  poured  into  a  bottle  together  and  well  shaken,  and 
this  operation  be  repeated  again  and  again  till  the  two  solutions  are  exhausted,  you  get 
a  perfect  emulsion  without  grain,  and  very  smooth.  It  will  be  noticed  that  in  this  plan 
the  silver  and  the  bromide  solutions  are  in  equal  quantities. — W.  ENGLAND. 

Another  plan  is  to  draw  out  two  funnels  to  fine  points  and  support  them  on  funnel- 
holders  over  a  jar.  These  are  filled  with  the  two  solutions,  which  are  allowed  to  run 
into  the  jar,  a  stirrer  being  used  to  aid  emulsification ;  other  workers  use  the  scent  dif- 
fuser,  by  which  to  secure  fineness  of  grain.  Any  of  these  artifices  may  be  employed.  A 
later  plan,  which  the  writer  has  adopted,  and  which  is  very  effective,  is  to  shake  the 
gelatine  containing  the  bromide  into  a  froth,  and  then  to  add  the  silver  nitrate  little  by 
little.  This  makes  a  beautifully  fine  emulsion,  and  seems  to  be  equiva- 
lent to  immersing  a  delicate  film  of  gelatine  into  a  silver  bath,  when 
we  know  that  splendid  films  are  to  be  obtained,  having  the  very  finest 
grain. — L.  WARNERKE. 

Many  of  the  difficulties  of  collodion  emulsion-making  may  be  over- 
come by  the  use  of  the  contrivance  I  describe  below.  1.  A  glass  bottle 
of  any  capacity  whatever,  intended  to  contain  the  bromized  collodion. 
2.  A  glass  balloon  for  the  solution  of  silver  nitrate.  (Fig.  310.) 

The  two  are  joined  together  by  means  of  a  long  cork.  This  cork  is 
perforated,  and  a  small  glass  tube  fixed  in  the  hole.  Supposing  that 
an  emulsion  is  to  be  made,  the  bromized  collodion  is  placed  in  the 
bottle  and  the  cork  introduced  (as  the  cork  is  long,  half  of  it  stands 
out  of  the  bottle) ;  the  nitrate  solution  is  introduced  into  the  balloon. 
The  bottle  is  now  turned  upside  down  (as  the  glass  tube  is  small,  no 
liquid  escapes  if  turned  with  care)  and  fitted  into  the  neck  of  the  bal- 
loon, which  is  immediately  turned  upwards.  Now,  if  the  apparatus 
be  shaken  with  force,  at  every  movement  a  few  drops  of  the  silver  solu- 
tion are  precipitated  into  the  collodion,  and  the  bromide  of  silver  is  thus 
slowly  formed  in  the  collodion.  The  shaking  is  continued  until  all 
the  nitrate  solution  has  made  its  way  into  the  collodion. — A.  DAVANNE. 
What  I  describe  below  is  an  apparatus  for  the  making  of  emulsions. 
It  can  also  be  employed  for  every  service  required  as  a  still,  such  as 
making  distilled  water,  distilling  alcohol  and  ether,  precipitating  cotton  for  emulsion 
work,  etc. 


FIG.  310. 


NEGATIVE- MA  KING  —  DRY. 


321 


I  have  heard  it  said  that  one  need  not  be  so  careful  in  this  matter,  but  I 
have  seen  many  bad  results  from  unclean  plates. 

Fig.  311  represents  said  apparatus  as  fitted  up  to  distil  water.  A  represents  a  copper 
boiler  on  which  is  firmly  screwed  by  means  of  clamping  screws,  a  dome  made  of  the 
same  metal.  BE'  two  funnel-shaped  holes  in  which  are  inserted  two  corks  or  India- 
rubber  plugs.  C  is  a  smaller  hole  stopped  with  a  cork,  the  use  of  which  will  be  seen 
hereafter. 

To  set  the  apparatus  at  work,  fill  up  the  boiler  with  the  exact  quantity  of  water  which 
the  large  bottle  D  can  hold.  Fit  into  plug  B  the  condensing  apparatus  E;  stop  up  the 
holes  in  the  plugs  B/  and  C  with  corks,  and  light  the  fire  or  gas  under  the  boiler;  by 
looking  at  the  bottle  D,  it  can  easily  be  seen  how  much  the  water  has  diminished  in  the 
boiler,  which  can  easily  be  refilled  if  required,  by  taking  out  the  cork  C,  and  putting  a 
funnel  in  its  place. 


Fm.  311. 


FIG.  312. 


Water  containing  alcohol,  the  product  obtained  in  precipitating  emulsions  or  collodion, 
must  be  distilled  in  this  manner  also ;  but  on  no  account  must  water  containing  a  mix^ 
ture  of  alcohol  and  ether  be  so  distilled;  we  shall  see  how  hereafter. 

I  will  now  give  a  description  of  the  apparatus  as  arranged  in  order  to  precipitate  collo- 
dion or  emulsions. 

As  may  be  seen  by  Fig.  312,  a  slight  addition  is  made  to  the  apparatus.  1.  G  is  a 
copper  boiler,  having  handles  on  the  sides,  and  near  the  bottom  an  opening  in  which  to 
insert  a  cork  bearing  a  thermometer,  G.  This  boiler  is  filled  about  quarter  full  of  water, 
and  when  the  still  is  introduced  it  displaces  the  water  and  forces  it  to  rise  to  the  level 
indicated.  A  second  addition  is  that  of  a  porcelain  pan  or  pail,  H,  which  is  placed  in 
the  middle  of  the  still  in  such  a  manner  that  a  certain  quantity  of  water  may  separate  it 
from  the  still.  A  centre  point  is  fixed  in  the  bottom  of  this  pan,  in  which  rotates  the 
lower  end  of  a  shaft  bearing  a  number  of  propellers  or  beaters,  /,  in  wrought  silver.  On 
the  top  of  the  shaft  is  fixed  a  handle,  J,  or  any  other  mechanical  contrivance  by  which 
the  beaters  can  be  made  to  rotate.  A  funnel  and  glass  tube  "tube  du  surete"  K,  in  a 
oork,  is  fixed  into  the  hole,  C,  in  the  dome,  to  enable  the  collodion  to  be  poured  slowly 

21 


322         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

150.  To  prepare  an  emulsion  with  ammonio-nitrate  of  silver  based  on 
Dr.  Eder's  plan — proceed  as  follows :  A.  Bromide  of  potassium,  370  grains ; 
gelatine,  518  to  694  grains;  pure  water,  10J  ounces.  B.  Nitrate  of  silver, 
458  grains ;  pure  water,  10J  ounces.  A.  should  first  be  dissolved. 

After  soaking,  say  fifteen  minutes,  place  the  ingredients  in  a  water-bath  at  a 
temperature  of  95°  to  120°  F.,  till  the  gelatine  has  dissolved,  and  the  solution 
is  clear.  Now  ammonia  is  added  drop  by  drop  to  B.  until  the  precipitate  first 

into  the  apparatus  E,  as  represented  in  Fig.  313,  is  this  time  passed  through  the  lower 
plug  B'. 

In  order  to  set  the  apparatus  at  work,  the  porcelain  pan  is  nearly  filled  with  distilled 
water,  in  fact  to  the  level  of  the  beaters,  and  is  then  fixed  in  the  middle  of  the  still, 
which  is  then  firmly  closed  by  means  of  the  clamping  screws. 

The  apparatus  now  being  ready  for  work,  is  placed  upon  a  gas  or  other  stove,  and  as 
soon  as  the  outside  thermometer  marks  150°  Fahrenheit,  which  supposes  the  heat  of  the 
water  in  the  interior  of  the  pan  sufficiently  hot  to  evaporate  ether,  the  fire  is  extinguished, 
and  the  collodion  or  prepared  emulsion  is  gradually  poured  into  the  interior  of  the 
apparatus  by  means  of  the  glass  tube  and  funnel  K.  In  coming  into  contact  with  the 
hot  distilled  water,  a  great  dilatation  takes  place  by  the  rapid  evaporation  of  the  ether ; 
at  the  same  moment  the  precipitated  cotton  is  drawn  violently  down  to  the  bottom  of  the 
water  by  the  movement  of  the  screw  or  beaters,  and  is  there  kept  in  constant  agitation. 
The  ether  makes  its  way  out  of  the  still  through  the  glass  tube  at  B',  is  condensed  in  the 
cooling  apparatus,  and  is  collected  in  a  bottle  about  a  quarter  full  of  distilled  water,  and 
left  there  until  a  certain  quantity  is  collected,  and  above  all,  to  extricate  any  alcohol 
which  has  made  its  way  out  of  the  still  in  company  with  the  ether.  As  for  myself,  after 
having  shaken  it  up  once  or  twice,  in  decanting  it  with  care,  I  find  it  sufficiently  pure  to 
make  normal  collodion.  Naturally,  if  a  great  purity  be  required,  it  must  be  washed 
several  times,  taking  care  to  diminish  the  quantity  of  water  each  time ;  a  tenth  of  the 
volume  is  sufficient  for  the  last  wash.  The  ether  is  then  put  into  a  bottle  containing 
chloride  of  calcium,  and  left  there  for  several  hours,  or  even  days,  and  then  distilled,  in 
the  same  apparatus  as  Fig.  313,  but  without  the  beaters. 

Let  us  return  to  the  precipitated  cotton ;  in  an  hour  the  water  is  sufficiently  cool  to 
dip  the  hands  into  it,  therefore  the  dome  is  detached,  and  the  porcelain  pan  containing 
the  precipitated  cotton  with  the  alcoholized  water  taken  out ;  this  is  poured  through  a 
fine  sieve  which  retains  the  cotton ;  the  water  is  set  aside  to  distil  the  alcohol  from  it, 
when  sufficient  is  obtained  to  pay  the  expense.  The  product,  pure  cotton,  or  cotton  con- 
taining bromide  of  silver,  is  then  washed  in  several  changes  of  water  (and  finally  I  give 
it  a  last  wash  in  alcohol),  and  then  it  is  set  aside  in  enamelled  iron  trays,  to  dry  sponta- 
neously. 

The  dry  product,  whether  it  be  precipitated  cotton  or  sensitized  cotton  obtained  by 
this  process,  has  a  honeycombed  appearance,  dissolves  readily  in  the  solvents,  and  gives 
a  very  pure  solution.— PROF.  E.  STEBBING. 

150.  I  have  introduced  a  stirring  apparatus  for  quantities  of  two  quarts  and  upwards. 
It  consists  of  a  hard-rubber  stirrer,  r,  dipping  into  the  solution  in  the  jar,  P,  and  turning 


NEGATIVE- MA  KING  —  DRY. 


323 


formed  is  redissolved  and  the  solution  is  clear.  These  operations  can  be  car- 
ried on  in  daylight.  Now,  to  the  dark-room  and  in  as  weak  a  ruby  light  as 
possible,  gradually  add  the  silver  solution  to  the  gelatine.  Shake  well  after 
the  addition  has  been  made,  at  intervals,  and  set  aside  to  cool.  Then  replace 
the  bottle  in  the  water-bath,  which  should  be  at  a  temperature  not  exceeding 
95° ;  let  it  remain  for  from  half  to  one  hour,  allowing  the  water  in  the  bath 
at  the  same  time  to  cool  down  gradually  to,  say,  75°,  not  lower.  The  tem- 
perature should  not  be  allowed  to  sink  so  low  as  that,  there  may  be  danger  of 

on  a  vertical  axis  supplied  with  a  bevelled  wheel,  r  r' .  The  axle  of  the  latter  is  connected 
with  a  multiplying  wheel  and  handle,  D  Jc.  For  preparing  large  quantities  of  emulsion  I 
recommend  steam-Jieating,  but  if  the  above  ap- 
paratus be  placed  over  a  fire,  it  will  be  well  to 
support  the  jar  Pon  two  iron  supports,  so  that 
the  hot  water  can  circulate  under  the  bottom ; 
otherwise,  the  bromide  of  silver  may  cake  fast 
to  the  bottom,  owing  to  its  being  more  heated 
than  the  sides.— DR.  H.  W.  VOGEL. 

For  a  rapid  emulsion  I  use  the  following 
with  much  success :  Nelson's  No.  1  gelatine,  80 
grains ;  Coignet's  Swiss,  or  any  good,  hard  gela- 
tine, 280  grains ;  nitrate  of  silver,  232  grains  ; 
bromide  of  potassium,  164  grains;  iodide  of 
potassium,  20  grains ;  strong  water  of  ammonia, 
1  drachm. 

The  sensitiveness  of  the  above  depends  upon 
its  subsequent  treatment. 

If  mixed  in  the  usual  manner — i.  e.,  the  silver 
dissolved  in  water  and  added  to  the  gelatine 
solution — a  plate  of  ordinary  rapidity  will  be  the 
result ;  but  if  the  silver  is  added  to  the  gelatine 
dry,  as  described  below,  much  greater  sensitive- 
ness will  be  obtained. 

Proceed  as  follows :  Dissolve  the  salts  in  five  ounces  of  water  and  add  the  minimum  of 
gelatine  (eighty  grains),  and  set  in  hot  water.  Weigh  out  the  silver  in  large  crystals. 
Put  the  same  in  a  strong  jug,  or  any  suitable  vessel.  Heat  both  the  jug  and  the  bromized 
gelatine  to  about  140°  or  150°  Fahr.  Carry  them  into  the  dark-room,  and  pour  the  gela- 
tine solution  as  quickly  as  possible  into  the  jug  and  upon  the  dry  silver.  Shake  rapidly 
till  dissolved,  after  which  replace  in  the  hot  water  and  bring  to  boiling  point.  If  boiled 
longer  than  thirty  minutes,  a  drop  or  two  of  nitric  acid  should  be  added.  In  the  mean- 
time the  remaining  gelatine  should  be  standing  in  sufficient  water  to  cover  well.  After 
sufficient  soaking  (an  hour,  more  or  less),  drain  the  water  all  away,  and  melt  slowly, 
keeping  the  temperature  down.  After  the  boiled  emulsion  has  cooled  to  about  90°  add 


324        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

the  gelatine  setting ;  bat  the  quantity  of  water  should  be  sufficient  to  prevent 
the  temperature  falling  lower  than  stated.  In  adding  ammonia,  which  should 
be  done  before  adding  the  silver  to  the  gelatine,  great  care  is  needed,  lest  the 
temperature  rise  too  high.  The  water-bath  should  be  watched  also,  for  too 
high  a  temperature  will  cause  fog  at  development.  The  danger  mark  is  ^00° 
to  105°. 

151.  When  the  digestion  is  complete  pour  the  emulsion  into  a  porcelain 
dish  and  place  it  in  cold  water  for  the  purpose  of  setting  it  quickly.  When 
thoroughly  set,  it  is  pressed  through  coarse  canvas,  and  then  suspended  in  a 
bag  and  washed  either  in  frequent  changes  of  water,  or,  better  still,  in  running 
water  for  from  four  to  five  hours.  As  the  emulsion  absorbs  a  good  deal  of 
water  during  the  washing,  the  latter  must  be  removed  either  by  allowing  it  to 
drain  for  some  time,  or  the  excess  may  be  expelled  either  by  gentle  pressure  or 
by  pouring  alcohol  over  the  emulsion.  In  the  latter  case  only  half  the  ordinary 
amount  of  alcohol  should  be  added  to  the  emulsion  after  filtering.  The  ernul- 

the  remaining  gelatine,  and  lastly  the  ammonia,  after  which  proceed  as  usual  with 
setting,  washing,  etc. — GEO.  SPERING. 

Great  care  is  necessary  all  through.  In  order  to  succeed,  it  is  necessary  to  have  the 
arrangements  of  the  dark-room  such  that  the  temperature  of  the  emulsion  and  freshly 
coated  plates  can  be  absolutely  under  control.  This  can  readily  be  attained  with  ice  and 
hot  water,  handled  with  judgment  and  a  little  ingenuity.  The  simpler  the  arrangements 
are,  however,  the  better,  as  there  is  then  less  danger  of  making  mistakes,  and  the  results 
will  be  more  uniform.  Any  good  operator  who  will  take  hold  of  the  matter  of  making 
his  own  plates  will  very  soon  be  able  to  produce  much  better  ones,  as  regards  both 
rapidity  and  quality,  than  any  of  the  commercial  brands  in  the  market,  for  the  reason 
that  he  will  do  his  own  work,  throughout,  and  will  do  it  in  all  of  its  points,  with  greater 
care  and  skill  than  the  hired  help  that  do  the  work  in  the  dry-plate  factories. — JAY 
DENSMORE.  * 

151.  The  changes  which  gelatine  undergoes  by  heating  and  putrefaction,  so  far  as  I 
have  been  able  to  determine,  are  as  follows : 

Gelatine  during  prolonged  digestion  splits  up  into  two  substances  —  semi-glutin 
(0551185^022),  insoluble  in  alcohol,  and  precipitated  by  platinic  chloride,  and  hemi- 
colline  (C47H70N14Oi9),  which  is  soluble  in  alcohol  and  not  affected  by  platinic  chloride. 
Semi-glutin,  by  standing,  reduces  silver  nitrate  without  precipitating  it,  while  hemi- 
colline  causes  a  flaky  precipitate  of  the  same.  This  splitting  up  of  the  gelatine  is  the 
reason  why  gelatine  after  long-continued  boiling  loses  its  setting  power,  without,  how- 
ever, any  decomposition  setting  in.  The  latter  is  only  apparent  after  several  days' 
boiling,  and  renders  the  gelatine  quite  fluid ;  but  boiling  for  a  half,  or  even  an  hour, 
does  not  produce  an  injurious  effect. 

If  gelatine  be  submitted  for  a  long  time  to  a  temperature  of  30°  C.  to  50°  C.,  it  loses 


NEGATIVE-MAKING  —  DRY.  325 

sion  may  now  be  melted  and  filtered,  or  any  sediment  may  be  allowed  to  sub- 
side to  the  bottom.  If  the  emulsion  is  to  be  preserved,  an  antiseptic  should  be 
added,  consisting  of  one  grain  of  salicylic  acid,  dissolved  in  alcohol,  to  every 
ounce  of  emulsion.  The  same  weight  of  oil  of  thyme — or,  best  of  all,  carbolic 
acid — may  be  substituted.  The  alcohol  serves  a  good  purpose  by  accelerating 
the  setting  of  the  emulsion. 

The  proportions  of  potassium  bromide  to  silver  nitrate  employed  should  not 
be  less  than  4  to  5.  With  less  bromide,  fog  is  apt  to  make  its  appearance. 
This  is  a  nice  point  and  requires  extreme  and  careful  attention.  As  Dr.  Eder 
truly  says : 

equally  its  setting  power ;  but  at  a  later  period  than  in  the  former  cases.  It  is  very  diffi- 
cult to  decide  the  exact  point  when  putrefaction,  shown  by  the  development  of  gas  and 
formation  of  ammonia  in  combination,  begins,  and  the  separation  above  alluded  to  ends. 

Boiling  with  even  a  slight  addition  of  ammonia,  or  of  acid,  quickly  deprives  gelatine, 
of  its  setting  powers,  and  the  same  splitting  up  appears  to  occur ;  at  all  events,  the  for- 
mation of  hemi-colline  is  apparent.  Gelatine  warmed  with  water  containing  one  or  two 
per  cent,  of  ammonia,  at  a  temperature  not  exceeding  40°  C.,  will,  at  the  end  of  three 
hours,  be  found  to  have  the  temperature  of  the  setting  point  lowered  to  1°  or  2°.  A  four 
per  cent,  solution  of  gelatine  digested  for  five  minutes  with  a  two  per  cent,  aqueous  solu- 
tion of  ammonia  at  temperatures  of  30°  C.  or  40°  C.,  has  its  setting  power  reduced  from 
5°  to  8°  C.,  and  after  three  hours'  digestion,  about  1°  C.  to  2°  C.  If  a  sample  of  gelatine 
is  too  soft,  alum  can  be  used  to  harden  it. 

The  fixed  alkalies  have  the  effect  of  decomposing  the  gelatine  when  boiled  with  them ; 
and  acid  potassium  bromide — as  might  have  been  expected — deprives  gelatine  of  its 
seting  power  more  rapidly  than  a  neutral  sample. 

This  loss  of  setting  power,  caused  by  heating  at  30°  C.  or  40°  C.  for  a  long  time,  is 
almost  always  the  result  of  decomposition.  Germs  of  putrefaction  are  always  present  in 
the  atmosphere,  so  that  no  artificial  ferment  is  necessary.  Decomposition  is  very  quickly 
set  up  by  the  addition  of  a  small  quantity  of  animal  tissue — for  instance,  muscular  tissue, 
or,  still  better,  the  substance  of  the  pancreas,  and  digesting  over  heat.  -According  to 
Weyl,  the  products  of  decomposition  caused  by  water  and  pancreas  are  alike. 

In  their  reaction  there  are  formed  from  every  100  parts  of  gelatine,  9.48  parts  of 
ammonia,  24.2  parts  of  volatile  fatty  acids,  12.2  parts  glycol,  19.4  parts  peptone,  and  6.45 
parts  carbonic  acid.  The  volatile  fatty  acids  are  acetic,  butyric,  and  valerianic  acid,  the 
first  of  these  being  more  abundantly  present  in  proportion  as  the  process  of  decompo- 
sition is  prolonged.  The  gas  given  off  does  not  consist  of  carbonic  acid  alone.  The 
ammonia  is  combined  with  the  fatty  acids,  and  remains  in  solution. 

Putrefaction  occurs  in  a  gelatine  solution  contained  in  a  close  vessel,  although,  under 
such  circumstances,  it  takes  about  six  times  as  long  to  develop  as  when  the  solution  is  in 
contact  with  the  atmosphere.  The  organisms  produced  during  the  progress  of  decom- 
position are  anaerobes,  which  are  capable  of  spontaneous  generation,  and  can  exist  apart 
from  contact  with  the  air. 


326        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

152.  "The  difficulty  of  determining  the  proper  proportions  depends  on  the 
fact  that  if  too  much  bromide  be  employed,  the  sensitiveness  is  reduced ;  if  too 
little,  there  is  a  danger  of  fog.  If  an  emulsion  containing  a  very  small  excess 
of  soluble  bromide  be  prepared  without  ammonia,  and  digested  for  several  days 
at  a  temperature  of  110°  or  120°  F.,  the  process  of  modification  proceeds 
rapidly,  and,  owing  to  the  low  temperature  employed,  there  is  very  little 
danger  of  decomposition.  If,  however,  the  operation  is  shortened  by  boiling 
or  addition  of  ammonia,  an  excess  of  soluble  bromide  is  very  useful  to  counter- 
act the  natural  tendency  to  fog.  In  case  of  long  digestion,  an  excess  of  soluble 
bromide  retards,  but  does  not  prevent  the  attainment  of  great  sensitiveness." 

The  conversion  of  the  insensitive  into  the  sensitive  modification  takes  place 
very  rapidly  if  the  directions  given  above  be  followed  out.     Even  at  a  tern- 
Gelatine  which  has  been  subject  to  decomposition  produces  fog  in  gelatino-bromide 
plates. — DR.  J.  M.  EDER. 

152.  The  amount  of  iodide  of  silver  which  has  so  far  been  employed  in  the  preparation 
of  gelatine  plates  is,  in  proportion  to  the  amount  of  bromine,  very  small,  but  greatly 
varying  in  the  different  formulae  put  forth.  The  amount  could  even  be  increased  in  the 
preparation  of  emulsion  for  ordinary  use.  The  results  of  the  two  might  be  compared. 

It  would  be  urged  that  it  is  very  difficult  to  prepare  a  gelatine  emulsion  containing 
iodide  of  silver  which  shall  possess  the  same  degree  of  fineness  as  one  containing  bromide 
of  silver.  It  will  be  found  to  be  much  coarser  in  grain. 

In  the  British  Journal  (June,  1884)  there  is  a  method  given  for  the  preparation  of  a 
very  fine  grained  iodide-bromide  of  silver  emulsion. 

It  is  this :  add  to  the  concentrated  gelatine  solution  first  the  silver  solution,  slightly 
acid ;  then  follow  the  iodide  solution,  which  it  is  most  advisable  to  mix  with  a  portion  of 
the  gelatine  solution,  and  last  of  all  the  bromide. 

By  this  plan  the  iodide  of  silver  comes  in  contact  with  an  excess  of  nitrate  of  silver, 
and  is  formed  into  a  concentrated  gelatine  solution.  This,  as  well  as  the  strong  dissolv- 
ing power  of  the  silver  nitrate,  acts  upon  the  iodide  of  silver  so  that  it  is  formed  much 
slower  and  in  a  much  finer  state  of  division. 

Another  method,  when  no  great  amount  of  iodide  of  silver  is  required,  is  as  follows : 
The  iodide  of  silver  is  precipitated  in  an  aqueous  solution,  dissolved  after  washing  in 
a  concentrated  silver  solution,  and  added  to  the  bromidized  gelatine  solution. 
If  a  pure  iodide  of  silver  emulsion  is  to  be  made,  the  following  plan  is  the  best  : 
Suppose  we  wish  150  c.  cm.  of  emulsion ;  weigh  out  100  grains  (6.2  grammes)  of  nitrate 
of  silver,  and  dissolve  it  in  60  c.  cm.  of  water,  to  which  50  grains  (3.1  grammes)  of  gelatine, 
and  2  drops  of  nitric  acid  are  added.     Next  dissolve  50  grains  (3.1  grammes)  of  gelatine 
and  40  grains  (2.5  grammes)  of  chloride  of  sodium  in  60  c.  cm.  of  water.   The  two  solutions 
are  mixed  and  stirred  well  together,  and  left  to  stand  in  a  warm  place  for  an  hour  to  set. 
A  chloride  of  silver  emulsion  is  obtained  in  this  way  with  such  a  fine  grain  that  the  film 
is  almost  transparent.    To  change  this  chloride  into  iodide  of  silver  emulsion  all  that  it 


NEGATIVE-MAKING  —  DRY  327 

perature  of  77°  F.,  the  operation  is  generally  complete  in  fifteen  or  twenty 
minutes.  If  a  small  portion  of  the  emulsion,  examined  on  a  strip  of  glass, 
transmits  blue  light,  the  digestion  may  be  stopped,  and  it  will  generally  be 
found  that  prolonging  the  digestion  over  thirty  minutes  does  not  give  material 
increase  of  sensitiveness,  although,  if  the  temperature  be  properly  controlled,  it 
may  be  continued  for  three  hours  without  any  decomposition. 

If,  when  the  emulsions  are  prepared,  the  solutions  are  too  hot,  or  dissolved 
silver  is  insufficiently  diluted,  or  the  quantity  of  gelatine  is  not  properly  pro- 
portioned, a  coarse-grained  emulsion,  without  any  corresponding  increase  of 
sensitiveness,  will  be  the  result.  Such  an  emulsion  would  be  useful  in  several 
of  the  heliographic  processes. 

153.  As  there  is  no  danger  of  the  emulsion  losing  its  setting  powers  under 

is  necessary  to  do  is  to  pour  a  solution  consisting  of  120  grains  (7.5  grammes)  of  iodide 
of  potassium  in  60  c.  cm.  of  water  upon  the  set  mass.  In  a  few  hours  the  decomposition 
of  the  chloride  of  silver  is  complete. 

The  precipitate  possesses  the  same  fineness  as  the  chloride  emulsion.  It  is  now  washed 
in  the  usual  manner.  The  operation  may  be  expedited,  and  the  decomposition  effected 
more  readily,  if  the  chloride  of  silver  emulsion  be  finely  divided  after  it  is  set,  and  in  this 
condition  treated  to  the  iodide  of  potassium  solution. 

This  iodide  of  silver  emulsion  may  be  used  alone,  or  in  union  with  bromide  of  silver 
emulsion. 

Comparative  experiments  could  be  better  conducted  in  this  manner  and  more  exact  than 
when  the  iodo-bromide  of  silver  emulsion  is  prepared  together. — DR.  C.  STURENBERG. 

At  first  I  used  to  add  the  iodide  after  the  silver,  but  after  some  experimental  work,  I 
now  dissolve  the  bromide  and  iodide  together,  and  see  no  difference  in  results.  A  good 
plan  to  get  a  fine  precipitate  is  to  filter  the  silver  into  the  iodo-bromized  gelatine,  with 
constant  stirring.  It  is  also  well  to  wash  the  sheets  of  gelatine  in  several  changes  of 
water  before  cooking  it.  In  this  way  we  reduce  the  chance  of  spots.  Keeping  emulsion 
a  full  week  before  use  is  far  better  than  using  it  up  immediately  after  it  is  made.  There 
is  less  chance  of  spots  by  this  procedure.  Immersing  plates  in  alum  before  fixing  is  far 
better  than  afterward. 

Common  china  or  earthenware  pots  are  very  handy  for  coating,  as  they  tend  to  hold 
back  any  froth  or  bubbles,  which  are  the  sorest  nuisance  in  emulsion  work.  Don't  use 
heat  in  drying  plates  after  coating.  Let  them  dry  spontaneously  in  a  cool  and  well- 
ventilated  room.  In  the  absence  of  such  a  room,  get  a  large,  light-tight  box,  or  chest, 
and  put  the  plates  in,  and  several  saucers  of  chloride  of  calcium,  which  will  absorb  the 
water  from  the  plates ;  they  will  dry  in  about  two  days.  Put  in  plenty  of  the  chloride 
of  calcium.  You  need  not  waste  it,  as  it  can  be  dried  again  over  a  kitchen  stove  and 
used  again  and  again. — RANALD  DOUGLAS. 

153.  In  choosing  gelatine,  note  the  following : 

When  ammonia  is  not  to  be  used,  the  gelatine  should  have  an  acid  reaction ;  when 


328        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

the  low  temperature  employed,  it  is  best  to  add  all  the  gelatine  at  once.  In 
emulsifying  with  ammonia,  it  is  never  advisable  to  add  a  second  quantity  of 
gelatine  to  the  emulsion  after  digestion,  owing  to  the  renewed  heating  which  is 
thus  entailed.  When  the  action  of  the  ammonia  is  too  prolonged,  especially 
in  summer  time,  frilling  is  very  apt  to  ensue. 

The  washing  of  the  emulsion  should  be  conducted  with  the  greatest  care,  as 
it  is  absolutely  impossible  to  attain  full  sensitiveness  in  the  presence  of  a  con- 
siderable excess  of  soluble  bromide;  and  if  any  trace  of  ammonia  be  left 
behind,  it  exercises  a  caustic  action,  and  combines  with  any  salicylic  acid  which 
may  afterward  be  added,  so  as  to  reduce  its  antiseptic  properties.  Never  forget 
that  an  unwashed  emulsion,  prepared  without  ammonia,  will  keep  fresh  for  a 
long  time  without  requiring  the  addition  of  an  antiseptic. 

In  proportioning  the  amount  of  gelatine  to  the  sensitive  salts,  it  has  been 
stated,  that  if  a  hard  gelatine,  possessed  of  great  power  of  resistance,  be  em- 
ammonia  is  used,  it  is  a  matter  of  indifference.  The  opinion  has  been  repeatedly  expressed 
in  English  journals,  that  the  clear  descriptions  of  gelatine  are  invariably  acid.  This  is 
only  in  a  certain  way.  All  alkaline  gelatines  that  I  have  come  across  were  cloudy ;  but 
all  acid  samples  were  not  clear  and  transparent. 

A  test  of  the  emulsion  at  a  temperature  of  40°  C.  can  be  made  by  means  of  silver 
bromide  and  ammonia. 

Ammonia  as  recommended  below  should  not  be  added  before  but  after  digestion,  and 
just  before  the  washing  stage.  A  plate  may  be  coated  with  the  unwashed  emulsion,  and, 
after  being  allowed  to  set,  may  be  soaked  in  water  for  twelve  hours.  When  dry  it  should 
be  treated  with  a  normal  developer,  and  give  clear  glass.  If  any  fogginess  is  apparent 
we  may  conclude  that  the  gelatine  employed  contains  injurious  by-products,  and  it 
should  be  rejected. 

Ordinary  collotype  gelatine  may  be  taken,  but  that  sort  is  to  be  preferred  which 
gives  the  clearest  and  hardest  jelly,  and  absorbs  little  water. 

The  gelatine  must  be  free  from  fat,  otherwise  there  will  be  depressions  in  the  film,  and 
bright  spots  with  blurred  outlines  in  the  negative.  A  gelatine  of  this  kind,  is  however, 
often  employed  when  the  emulsion  is  prepared  with  the  addition  of  ammonia.  In  this 
case  the  fatty  matter  is  probably  saponified,  and  the  spots  will  disappear. 

A  four  per  cent,  solution  of  gelatine  sets  thoroughly  at  a  temperature  of  about  20° 
C.  Since  this  corresponds  to  a  melting  point  of  about  28°  C.  or  30°  C.,  it  is  now  an  easy 
matter  to  determine  roughly  the  melting  points  of  various  sorts  of  gelatine,  and  to  infer 
that  the  setting  points  will  be  some  8°  C.  or  10°  C.  lower.  The  higher  the  melting  and 
setting  points  are,  the  better  is  the  gelatine,  so  long  as  it  dissolves  thoroughly  in  water 
at  a  temperature  of  40°  C.  or  50°  C. — DR.  J.  M.  EDER. 

One  fact  must  also  be  recollected,  that  frequent  reheating  of  gelatine  speedily  detracts 
from  its  setting  powers,  and  that  if  too  little  water  be  added  to  it  in  mixing,  the  film  has 
a  great  tendency  to  become  leathery,  more  particularly  if  a  little  chrome  alum  has  been 


NEGATIVE-MAKING  —  DRY.  329 

ployed,  less  is  required  than  when  a  softer  sample  is  made  use  of.  A  small 
proportion  of  gelatine  is  to  be  recommended,  for  the  following  reasons  :  The 
emulsion,  when  broken  up  into  small  pieces,  does  not  absorb  so  much  water 
during  washing.  When  the  emulsion  is  rich  in  bromide  of  silver,  there  is  no 
necessity  for  using  thick  films,  which,  besides  being  liable  to  frill,  take  a  much 
longer  time  to  dry  than  thin  ones.  If,  on  the  other  hand,  the  proportion  of 
gelatine  be  too  small,  the  bromide  of  silver  is  coarse  in  the  grain,  and  sinks  to 
the  bottom  of  the  emulsion.  In  preparing  a  hard,  quick-acting  emulsion, 
employ  a  large  proportion  of  potassium  bromide,  a  given  quantity  of  gelatine, 
and  one  and  a  half  times  its  weight  of  silver  nitrate.  Dr.  Van  Monckhoven 
rightly  remarks  that  a  large  proportion  of  gelatine  gives  a  soft  image ;  a  small 
proportion  a  denser  but  harder  picture. 

154.  When  preparing  an  emulsion  by  boiling,  and  subsequent  digestion 
with  ammonia,  the  following  hints  must  be  regarded. 

added  to  it  to  prevent  frilling.  A  judicious  mixture  of  alcohol  to  a  gelatine  solution 
increases  permeability  and  should  not  be  neglected.  The  use  of  a  sufficient  quantity  of 
water  is,  however,  the  great  desideratum,  and  should  be  carefully  attended  to,  the  quan- 
tity, of  course,  depending  on  the  temperature  at  which  the  plates  have  to  be  prepared  ; 
thus  in  winter  more  water  should  be  used  than  in  summer.  A  very  horny,  glassy  film  is 
objectionable  in  many  ways,  and  a  matt  surface  for  the  plates  should  be  aimed  at.  This 
depends  almost  entirely  on  the  gelatine  that  is  used,  unless  it  be  modified  by  additions 
such  as  glycerine,  to  which  we  may  at  once  say  we  object,  on  account  of  its  affinity  for 
water. — CAPT.  ABNEY. 

154.  The  sensitiveness  of  a  gelatine  emulsion  is  increased  not  only  by  long-continued 
heating,  by  which  the  gelatine  is  partially  decomposed,  but  also  by  boiling  for  not  more 
than  a  quarter  of  an  hour,  when  no  alteration  of  the  gelatine  can  be  observed.  Still  more 
powerful  is  the  fact  that  an  emulsion  of  gum-arabic  will  also  be  made  more  sensitive  both 
by  long-continued  digestion  at  a  moderate  temperature,  as  well  as  by  boiling  a  short  time. 
Now,  gum-arabic  does  not  alter  in  burning;  we  may  conclude,  therefore,  that,  in  all  these 
cases,  the  increased  sensitiveness  is  due  to  a  change  in  the  physical  condition  of  the 
silver  bromide.  Many  samples  of  gelatine  contain  substances  of  unknown  composition, 
which,  in  the  presence  of  ammonia,  reduce  bromide  of  silver,  and  give  rise  to  a  foggy 
emulsion.  Such  samples  of  gelatine  should  be  avoided. 

Another  factor  in  the  attainment  of  increased  sensitiveness  m'ay  possibly  be,  as  pointed 
out  by  Dr.  Lohse,  the  degree  of  porosity  of  the  gelatine  film.  Substances  which,  like 
alum,  have  a  tanning  action,  make  the  film  leathery  and  impervious,  and  a  less  sensitive 
plate  is  the  consequence.  Under  ordinary  circumstances,  however,  I  do  not  think  this 
difference  is  sufficiently  great  to  be  observable  in  practice.  At  any  rate,  I  have  not 
remarked  any  considerable  difference  in  this  respect  between  a  hard  collotype  gelatine 
and  a  soft  and  fine  sample,  though  comparative  toughness  of  the  two  was  just  as  marked 
after  they  had  been  treated  in  the  usual  way  with  ammonia. — DR.  J.  M.  EDER. 


330        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

This  method  gives  more  sensitive  plates,  but  requires  greater  care,  than  the 
preceding.  It  depends  on  the  fact  that  the  sensitive  modification  of  bromide 
of  silver  forms  very  rapidly  at  temperatures  between  140°  to  212°  F.,  and 
that  the  sensitiveness  of  such  an  emulsion,  in  itself  very  great,  can  be  still 
further  increased  by  subsequent  treatment  with  ammonia  at  a  low  temperature. 

The  proportions  of  the  ingredients  are  the  same  as  those  previously  given  : 
370  grains  of  potassium  bromide,  which  should  not  be  alkaline,  are  dissolved 
in  10 J  ounces  of  water,  in  a  strong  glass  bottle,  and  518  to  694  grains  of 
gelatine  introduced.  The  whole,  after  soaking  for  some  time,  is  dissolved  in 
hot  water,  at  a  temperature  of  95°  to  120°  F.  The  remaining  operations 
must  be  conducted  in  the  dark  room.  To  the  warm  solution  of  bromized 
gelatine  add  458  grains  of  nitrate  of  silver  previously  dissolved  in  10J  ounces 
of  water.  The  latter  may  also  be  warmed  over  the  water  bath.  There  is  no 
absolute  necessity  for  this  proceeding.  Now  wrap  the  bottle  in  a  thick  cloth, 
and  shake  well,  taking  care  that  the  cork  is  not  blown  out  by  the  steam.  The 
remainder  of  the  silver  may  be  rinsed  out  with  about  two  ounces  of  water. 
Finally,  1  to  2  grammes  of  potassium  iodide,  dissolved  in  a  little  water,  are 
added  to  produce  a  clearer  film.  During  the  boiling  which  follows,  the  cork 
must  not  be  pushed  in  too  tightly,  otherwise  the  pressure  of  steam  might  break 
the  bottle.  A  roll  of  linen  will  prevent  the  bottle  coming  in  contact  with  the 
heated  surface  of  the  bottom  of  the  saucepan.  The  best  way  is  to  replace  the 
cork  during  boiling  by  another  in  which  a  small  groove  has  been  cut  for  the 
escape  of  the  steam.  The  bottle  containing  the  emulsion  is  put  into  a  sauce- 
pan, covered  by  a  tightly  fitting  lid,  and  the  spirit  lamp  or  gas  jet  light  below, 
care  being  taken  that  not  even  the  reflected  light  from  the  flame  falls  upon 
the  emulsion.  The  water  bath,  which  should  contain  hot  water,  can  soon  be 
brought  to  boiling  point,  at  which  temperature  the  emulsion  should  remain  for 
twenty  or  thirty  minutes,  after  which  it  may  be  allowed  to  cool  down.  When 

Boiling  the  Emulsion. — A  saucepan  of  sufficient  size  to  hold  the  bottle  must  be  procured 
and  filled  with  water  to  a  convenient  height,  and  a  flame,  such  as  a  gas-burner,  placed 
beneath  it.  To  prevent  bumping  and  breaking  the  bottle,  place  half  a  dozen  folds  of 
blotting  paper  at  the  bottom  of  the  saucepan.  After  the  water  has  been  brought  to  a 
boiling  point  the  emulsion  is  kept  boiling  for  twenty  minutes  to  half  an  honr,  it  being 
shaken  at  intervals  (say  once  every  ten  minutes)  for  half  a  minute  or  so.  A  thick  cloth 
tied  around  the  hand  prevents  any  scalding.  The  boiling,  by  the  by,  should  take  place 
without  the  cork  being  left  in  the  bottle,  for  if  it  remain  in  it  would  be  blown  out  by  the 
force  of  the  steam.  A  cork  with  a  slot  cut  in  it  is,  however,  not  open  to  objection.— C APT. 
ABNEY. 


NEGATIVE-MAKING — DRY.  331 

large  quantities  of  emulsion  are  being  prepared,  the  boiling  should  be  con- 
tinued longer.  The  necessary  time  of  boiling  must  be  reckoned  from  the 
moment  that  the  emulsion  reaches  a  temperature  of  50°  C.  If  the  emulsion 
is  very  acid,  such  as  occurs  when  ammonium  bromide  is  employed,  the  boiling 
may  be  continued  for  an  hour  without  damage,  and  with  a  resulting  increase 
of  sensitiveness.  But  as  gelatine  boiled  in  the  presence  of  an  acid  is  apt  to 
decompose,  only  a  small  portion  of  the  gelatine  should  be  used,  and  the  bulk 
added  afterward. 

155.  The  emulsion  at  this  stage  will  be  found  extremely  sensitive,  and  can 
be  used  as  it  is;  but  by  further  treatment  with  ammonia,  it  is  possible  to 
increase  the  sensitiveness  considerably. 

155.  Cooling  and  Washing  the  Emulsion. — After  the  proper  time  of  boiling  the  saucepan 
is  removed.  The  gelatines  Nos.  5  and  6  should  in  the  interval  be  rapidly  rinsed  in 
several  changes  of  water  to  get  rid  of  any  adherent  dust.  They  should  then  be  placed 
in  a  pot  with  two  ounces  of  cold  water  and  allowed  to  swell.  After  this  they  are  melted 
at  a  temperature  of  about  100°  F.,  by  immersing  the  pot  or  flask  in  hot  water,  and  added 
to  the  solution  in  the  bottle.  Both  the  emulsion  and  also  the  dissolved  gelatine  should  be 
cooled  to  about  70°  to  80°  F.  by  allowing  water  from  the  tap  to  run  over  the  .jar  before 
the  addition  is  made. 

After  a  good  mixing,  by  shaking,  the  froth  is  left  to  subside  and  the  emulsion  is  poured 
out  into  a  flat  porcelain  dish  and  allowed  to  rest.  The  time  which  it  will  take  will  vary 
according  to  the  temperature  of  the  surrounding  air,  but  a  couple  of  hours  are  generally 
amply  sufficient,  and  often  a  much  less  time  will  suffice.  In  very  hot  weather,  if  the  dish 
be  stood  in  iced  water,  no  difficulty  in  setting  will  be  found.  After  a  proper  consistency 
is  obtained  (such  consistency  being  that  the  gelatine  should  not  tear  with  a  moderate 
pressure  of  the  finger)  the  emulsion  is  carefully  scraped  off  the  bottom  of  the  dish  with 
a  strip  of  clean  glass  and  transferred  to  a  piece  of  very  coarse  canvas  which  has  been 
previously  boiled  in  water  to  get  rid  of  any  grease  or  dirt.  The  emulsion  is  then  twisted 
up  in  this  and  by  a  gentle  pressure  squeezed  through  the  interstices,  the  ball  of  emulsion 
being  absolutely  below  the  surface  of  the  water  into  which  it  is  forced.  The  water  causes 
the  threads  of  gelatine  to  remain  tolerably  separate,  and,  as  it  passes  through  the  liquid, 
most  of  the  soluble  salts  are  at  once  extracted. 

When  all  is  squeezed  through,  the  particles  of  gelatine  may  again  be  transferred  to  the 
canvas,  and,  after  stretching  it  loosely  over  the  mouth  of  the  jar  (emptied  of  water),  may 
be  doused  with  water  from  the  tap  or  from  a  water  jug.  After  a  couple  of  gallons  have 
been  thus  passed  over  it,  the  emulsion  should  again  be  squeezed  through  the  canvas,  and 
the  same  operation  repeated,  thus  exposing  fresh  surfaces  of  gelatine  to  the  action  of  the 
water.  After  another  sluicing  with  water  the  emulsion  may  be  considered  as  washed, 
though,  to  make  assurance  doubly  sure,  the  gelatine  may  be  left  at  the  bottom  of  the  jar, 
and  the  water  changed  two  or  three  times.  To  show  the  importance  of  thorough  wash- 
ing, the  following  experiment  may  be  noted.  An  emulsion  was  made  as  above,  and, 
after  once  squeezing  through  the  canvas,  a  part  was  immediately  used  for  making  plates. 


332        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

When  the  temperature  has  fallen  to  about  40°  F.,  two  drachms  of  strong 
ammonia  (sp.  gr.  0.910)  are  added,  and  the  emulsion  is  digested  for  half  an 
hour  or  an  hour  at  a  temperature  of  95°  to  100°  F.  Then  the  emulsion  is 
ready  for  washing,  which  may  be  carried  out  in  the  same  manner  as  already 
described. 

Dr.  Eder  claims  that  an  emulsion  prepared  in  this  way  is,  perhaps,  one-fifth 
more  sensitive  than  one  prepared  according  to  the  preceding.  It  gives  well- 
graded  harmonious  pictures,  free  from  tendency  to  hardness.  The  picture  ap- 
pears readily  under  the  developer.  The  details  in  the  shadows  should  be  fully 
developed  before  the  high  lights  are  too  dense.  Emulsions  produced  by  this 
method  are  specially  suitable  for  portraiture,  although  they  do  not  give  such 
absolutely  clear  glass  in  the  shadows  as  can  be  obtained  by  the  first  method. 
By  this  method  extreme  care  should  be  exercised  in  the  choice  of  materials. 

A  second  part  of  the  same  was  washed  under  the  tap  for  five  minutes ;  a  third  part  was 
squeezed  and  washed  a  second  time ;  and  a  fourth  part  was  allowed  to  soak,  and  squeezed 
a  third  time.  The  relative  sensitiveness  of  the  four  parts  was  as  follows:  1 — 1J — 2£ — 2}. 

The  first  washing  increased  the  sensitiveness  to  one  and  a  half,  and  the  second  squeez- 
ing to  two  and  a  half,  while  the  third  squeezing  and  washing  had  no  perceptible  effect. 

I  consider  this  method  of  washing  superior  to  those  which  follow.  Two  squeezes,  it  is 
believed,  are  equal  to  twenty-four  hours'  such  washing.  Gelatine  is  hard  to  permeate, 
and,  being  a  colloidal  body,  the  crystalline  salt  has  hard  work  to  get  through  when  the 
emulsion  is  not  finely  broken  up. — CAPT.  ABNEY. 

Draining  the  Emulsion. — When  the  emulsion  is  considered  to  be  properly  washed,  it  is 
then  drained.  This  I  generally  do  over  the  canvas,  though  some  recommend  a  hair  sieve, 
but  it  does  not  appear  that  there  is  much  advantage  to  be  derived  from  its  use.  The 
great  point  in  either  case  is  to  drain  long  enough.  A  couple  of  hours  is  sufficient  time, 
and  then  the  emulsion  is  ready  for  melting. 

It  will  sometimes  happen  that  no  amount  of  draining  over  a  hair  sieve  or  canvas  will 
render  the  emulsion  sufficiently  free  from  water  to  set  well  when  dissolved  up.  I  have 
found  that  by  pouring  a  couple  of  ounces  of  alcohol  through  the  emulsion  when  drain- 
ing, that  the  excess  of  water  is  taken  up  and  it  becomes  firm.  It  should  be  noticed  that 
before  redissolving  the  gelatine  it  should  be  firm  and  free  from  all  sloppiness  (if  such  an 
expression  may  be  used) ;  one  dose  of  alcohol  generally  effects  this,  and  if  not  one,  two 
will.  The  alcohol  may  be  saved  if  required.  In  case  this  artifice  be  resorted  to,  only 
half  the  quantity  of  alcohol  should  be  added  to  the  emulsion  when  it  is  redissolved  for 
filtering  and  coating  the  plates.  Emulsion  that  is  cut  up  into  shreds  is  much  more  easily 
drained  than  that  which  is  squeezed  through  the  canvas.  It  is  not  that  the  gelatine 
takes  up  more  water,  but  that  the  water  clings  mechanically  to  the  small  particles  form- 
ing it.  I  recommend  that  the  canvas  be  as  coarse  as  possible,  having  a  mesh  not  less 
than  one-eighth  of  an  inch,  if  such  can  be  procured. 

Dissolving  the  Emulsion. — After  draining,  the  emulsion  should  be  transferred  to  a  clean 


NEGATIVE-MAKING — DRY.  333 

The  gelatine  and  bromide  should  not  be  alkaline,  otherwise  there  is  danger 
of  fog  during  the  boiling.  If  a  difficulty  is  experienced  in  procuring  neutral, 
or  slightly  acid,  materials,  the  warm  solution  of  potassium  bromide  and  gelatine 
may  be  cautiously  acidified  with  dilute  acetic  acid.  The  condition  of  the 
mixture  must  be  only  very  slightly  acid,  otherwise  the  setting  power  of  the 
gelatine  will  be  impaired.  Warming  the  bromide  gelatine  as  recommended, 
before  the  introduction  of  the  nitrate  of  silver,  hastens  the  operations  con- 
siderably. Half  an  hour  is  the  most  suitable  period  for  the  boiling,  a  quarter 
of  an  hour  being  hardly  sufficient ;  while,  if  the  operation  is  prolonged  to  three- 
quarters  of  an  hour,  fog  sometimes  ensues.  Some  samples  of  gelatine  will 
admit  of  longer  boiling  than  others.  Generally  speaking,  the  emulsion  may 
be  boiled  so  long  as  it  remains  clear,  and  the  longer  it  is  boiled  the  more  sen- 
sitive it  will  be. 

156.  In  digesting  an  emulsion  with  ammonia,  special  care  must  be  taken  as 
to  the  temperature  indicated.  Generally  speaking,  half  an  hour's  digestion 

jar  or  jam  pot,  and  then  placed  in  boiling  water  until  all  the  gelatine  is  thoroughly 
dissolved.  A  temperature  of  120°  F.  or  more  may  be  given  it  with  advantage.  The 
emulsion,  when  all  additions  are  made,  will  be  about  six  and  a  half  ounces.  The 
addition  of  one-half  grain  of  chrome  alum  is  to  be  recommended.  This  should  be  dis- 
solved in  one  drachm  of  water  and  added  with  stirring ;  six  drachms  of  absolute  alcohol 
are  next  to  be  added  in  the  same  way,  and  the  emulsion  is  then  ready  for  filtering.  This 
operation  may  be  carried  out  in  various  ways.  I  now  use  wet  chamois  leather,  or  swans- 
down  calico  which  has  previously  been  well  boiled  and  washed.  This  is  allowed  to  rest 
loosely  in  a  funnel,  and  the  emulsion  filters  slowly  through  it,  all  coarse  particles  being 
left  behind.  A  small  plug  of  washed  wool  is  used  by  many,  and  answers  well.  It  is 
preferable  to  filter  into  a  Florence  flask,  as  it  will  bear  heat,  though  an  ordinary  medi- 
cine bottle  will  answer  if  the  flask  be  not  at  hand.  The  bottle  or  flask  is  again  placed 
in  water  at  a  temperature  of  129°  F.,  and  the  next  operation  is  to  coat  the  plates. 

156.  The  effect  of  the  temperature  at  which  the  plates  are  dried  on  the  modification  of 
their  sensitiveness  should  not  be  overlooked.  From  experiments  made  on  this  subject 
in  the  case  of  very  rapid  emulsions,  the  bromide  of  silver  exists  under  a  form  in  which 
its  sensitiveness  is  easily  modified  by  pressure,  or  some  other  influence.  The  sensitive- 
ness may  be  impaired  to  a  visible  degree,  simply  by  the  temperature  at  which  the  plates 
have  been  dried.  Even  between  the  ordinary  limits — that  is  to  say,  between  10°  and 
22°C.  (50°  to  71°  F.) — variations  of  sensitiveness  have  been  found  in  the  ratio  of  2  to  3 
tot  I. 

The  plates  dried  at  a  low  temperature  develop  more  rapidly  than  those  developed  at 
a  high  temperature.  From  these  experiments,  the  lower  the  drying  temperature,  the 
better.  It  has  been  observed,  however,  that  up  to  16°  C.  (60°  F.)  there  is  no  falling  off 
of  the  sensitiveness.— ANONYMOUS. 


334        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

will  be  sufficient,  but  the  operation  can  be  continued  for  an  hour,  and  even 
two  hours,  without  danger,  and  there  is  more  certainty  that  the  desired  sen- 
sitiveness will  be  attained.  Besides  this,  the  subsequent  treatment  with  am- 
monia compensates  for  any  defect  in  the  boiling  during  the  first  part  of  the 
process.  The  same  precautions  recommended  under  the  first  method,  in  regard 
to  the  addition  of  ammonia,  are  applicable  in  this  case.  In  both  methods  it  is 
directed  that  all  the  gelatine  should  be  added  at  the  outset.  With  some  samples 
of  gelatine  easily  acted  upon,  it  may  be  found  necessary  only  to  add  part  of  the 
gelatine  at  first,  and  the  remainder  after  the  digestion  is  completed.  Gelatine 
being  the  most  obstreperous  ingredient  in  use,  a  modification  of  treatment  may 
be  required  by  every  lot  used. 

157.  For  the  preparation  of  an  emulsion  by  digestion  at  low  temperature 
proceed  as  follows : 

Although  the  methods  given  above  are  reliable,  yet,  owing  to  the  extreme 
care  required  in  the  manipulations,  and  the  danger  of  fog  from  the  use  of 
unsuitable  materials,  it  is  thought  best  to  give  another  formula  which  may  be 
absolutely  relied  upon  even  in  unskilled  hands. 

After  what  has  already  been  said  on  the  subject,  I  may  give  the  formula  in 
a  few  words :  370  grains  of  bromide  of  potassium  and  617  grains  of  gelatine 
are  dissolved  by  heat  in  10  J  ounces  of  water,  and,  as  soon  as  the  solution  is 
complete,  the  temperature  of  the  mixture  is  raised  to  120°  F.,  and  a  solution 
of  463  grains  of  nitrate  of  silver  in  10  J  ounces  of  water  is  introduced.  The 
emulsion  is  placed  in  a  water  bath  at  a  low  temperature,  viz.,  90°  F.,  and 
digested  at  this  temperature.  It  is  well  to  keep  back  half  the  gelatine  till  after 
digestion. 

If  an  emulsion  is  required  about  as  sensitive,  or  twice  as  sensitive,  as  wet 

157.  Frilling. — Gelatine  films  on  glass  have  occasionally  a  very  awkward  way  of 
expanding,  and  forming  frills  and  blisters  when  heated  with  water,  especially  when  the 
water  contains  salts  in  solution.  Frilling  and  expansion  of  the  film  are  also  promoted — 
1,  by  coating  the  plates  thickly;  2,  when  the  gelatine  absorbs  a  good  deal  of  water; 
3,  when  the  emulsion  has  been  digested  a  long  time  over  heat;  4,  when  the  gelatine 
contains  gum-arabic. 

The  first  of  these  faults  can  be  cured  by  coating  the  plates  more  thinly ;  the  second  by 
addition  of  alum  or  chrome  alum,  or  by  soaking  the  plate  before  development  in  a  cold 
saturated  solution  of  alum.  The  latter  is  generally  efficacious,  if  the  plate  be  developed 
immediately  after  coming  out  of  the  alum  bath.  If  this  fails  the  plate  may  be  rinsed 
and  dried,  and  then  developed.  By  this  means  the  absorptive  power  of  gelatine  is  a 
good  deal  diminished. — DR.  J.  M.  EDER. 


NEGATIVE- MAKING  —  DRY. 


335 


FIG.  314. 


collodion,  it  may  be  used  after  six  to  twelve  hours'  digestion.  Such  an  emul- 
sion is  very  well  adapted  for  landscapes  or  interiors. 

If  a  more  sensitive  preparation  is  required,  the  digestion  may  be  continued 
for  three  days  at  a  temperature  of  90°  F.  The  resulting  emulsion  will  be 
very  sensitive,  and  well  adapted  for  portraiture,  as  it  gives  soft,  harmonious 
negatives.  It  may  be  looked  on  as  one  of  normal  sensitiveness. 

158.  Dr.  Eder  says  :  "  No  doubt  the  best  method  of  washing  emulsion  is  to 

158.  There  are  several  modes  of  extracting  the  soluble  salts  from  the  emulsion.  Put- 
ting on  one  side  dialysis  as  introduced  by  Mr.  King,  owing  to  its  tediousness,  we  pass 
on  to  the  most  ordinary  method.  The  emulsion,  when  prepared,  is  poured  out  into  a 
flat  dish  in  a  very  thin  layer,  say  about  one-eighth  of  an  inch  thick.  When  set,  it  is 
scraped  off  the  dish  with  a  piece  of  glass,  and  transferred  to  a  jar 
or  bottle  in  strips.  Mr.  England  first  scores  it  over  with  the  prongs 
of  a  silver  fork,  so  breaking  it  up  into  fine  strips.  Cold  water  is 
then  poured  on  to  it,  and  a  stream  of  running  water  kept  flowing 
over  it  for  twelve  hours,  more  or  less. 

I  have  converted  a  tin  canister  into  an  effective  washing  appa- 
ratus, as  shown  in  the  figure.  In  the  lid  of  a  common  canister  a 
hole  is  perforated  so  as  just  to  admit  of  the  insertion  of  a  glass 
tube,  a,  a;  a  piece  of  India-rubber  tubing  connects  this  with  the 
water  tap,  and  covers  any  small  chink  between  the  glass  and  the 
lid,  as  shown.  A  bottle  containing  the  emulsion  to  be  washed  is 
placed  in  the  canister,  the  tube  being  inserted  in  it.  The  water 
flows  over  the  top  of  the  bottle  and  rises  in  the  canister  to  the 
level  of  the  spout,  where  it  trickles  over  into  the  sink;  the  heavy 
water  containing  the  soluble  nitrate  is  thus  perpetually  stirred  up, 
and  caused  to  flow  over  the  neck  of  the  bottle.  This  answers  ad- 
mirably, and  can  be  used  in  the  daylight  if  necessary,  but  is  more 
applicable  to  emulsion  that  has  been  cut  into  strips  than  to  that  which  has  been  squeezed 
twice,  as  the  small  particles  are  apt  to  be  carried  over  the  top  of  the  bottle  and  choke 
the  exit  tube. 

After  the  emulsion  has  been  allowed  to  rest  for  two  or  three  hours,  two  ounces  of 
alcohol  to  each  ounce  of  water  are  poured  into  the  bottle  containing  it,  and  well  shaken 
up.  The  gelatine  rapidly  assumes  a  pasty  appearance,  and  subsides  to  the  bottom.  The 
bottle  is  then  inverted,  and  the  fluid,  which  contains  the  soluble  nitrates  and  excess  of 
water,  is  poured  off,  and  may  be  preserved  for  distillation.  The  explanation  of  the  effi- 
cacy of  this  method  is,  that  the  alcohol  has  a  greater  affinity  for  water  than  has  the 
gelatine,  and  that  in  extracting  the  water  the  soluble  salts  are  extracted  with  it.  Methy- 
lated spirit  not  containing  gum  may  be  used,  and  the  lower  the  specific  gravity  the  more 
effectual  it  is. — WRATTEN  and  WAINWRIGHT. 

After  the  emulsion  is  settled,  drain  off  the  water  into  another  vessel  so  as  to  catch  any 
stray  particles  that  would  otherwise  be  lost.  A  second  change  of  water  is  now  poured 


336 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  315. 


first  break  it  up  into  small  pieces  ;  but  as,  in  this  state,  it  absorbs  a  large  quantity 
of  water,  I  give  a  method  recommended  by  Heid.  The  emulsion  is  poured 

on  the  emulsion  and  well  stirred  up  with  the  glass  rod,  the  whole  again  allowed  to  settle, 
and  this  is  repeated  six  times.  Finally  it  is  treated  with  distilled  water  twice,  and  tested 
for  free  soluble  bromide  by  adding  a  few  drops  of  a  ten  per  cent,  solution  of  nitrate  of 
silver  to  the  last  drainings  from  the  emulsion.  If  a  decided  milkiness  is  seen  after  a  few 
minutes'  standing,  the  washing  must  be  continued  (with  distilled  water)  until  it  no 
longer  appears. 

I  have  succeeded  in  this  way  with  quantities  measuring  more  than  two  quarts.  At- 
tempts have  been  made  to  simplify  the  process  by  washing-machines,  but  these  have 
disadvantages. 

The  divided  emulsion  is  best  put  into  a  large  bag  made  of  coarse  silk,  and  hung  over 
a  cross-stick  in  a  small  tub  or  capacious  glass  vessel.  If  the  tub  is  very  roomy,  two 
hours'  washing  with  two  changes  of  water  and  an  occasional  shaking  up  of  the  bag  will 
be  enough.  With  smaller  vessels  four  changes  may  be  given.  Schuman's  apparatus 
(Eder)  is  also  very  practical  (Fig.  315).  A  pear-shaped  bell-glass  is  covered  at  its  nar- 
rower end  with  stout  muslin  to  support  the  emulsion,  and  the  whole  set  in  a  roomy 

beaker,  as  seen  in  the  figure.    To  change  the  water,  it  is  only 

necessary  to  lift  the  bell-glass,  when,  by  slightly  agitating  it,  the 

water  drains  off  through  the  muslin.    The  beaker  is  then  emptied 

and  refilled  with  fresh  water. 

Costly  and  complicated  affairs  for  washing  in  running  water 

have  also  been  made,  but  they  are  not  necessary.     For  operations 

on  the  small  scale,  a  large  china  or  porce- 
lain teapot  (not  metallic)  does  good  service. 

The  cover  is  replaced  by  the  layer  of  silk, 

and  a  rubber  tube  carried  from  the  tap 

to  the  spout;  the  water,  after  circulating 

through  the  pot,  escaping  through  the  silk 

fold.    The   emulsion   is    kept   constantly 

moving,  and  is  washed  very  quickly. 

Turnbull's  washing  apparatus,  or  one  on 

the  same  principle,  may  be  made  of  any  size;  its  construction  is 
easily  understood  from  Fig.  316.  The  water  is  conducted  to  the 
bottom  of  the  vessel  by  the  tube  D  F,  flowing  off  again  through 
the  funnel  B,  closed  with  silk,  so  as  to  prevent  the  escape  of  the 
small  particles  of  emulsion,  the  tube  c  serving  as  the  outlet. 
Eder  holds  that  an  emulsion  which  still  contains  0.1  per  cent, 
of  soluble  bromide  has  been  sufficiently  washed.  He  recom- 
mends this  test  for  the  washed  emulsion:  Prepare  a  solution 
of  exactly  61  §  grains  (4  grammes)  of  nitrate  of  silver  in  2.1 
pints  (1  litre)  of  distilled  water.  385  grains  of  the  emulsion  in  the 
liquid  state  are  weighed  out,  diluted  with  4  or  5  volumes  of  distilled  water,  and  after 
cooling  treated  with  yellow  chromate  of  potash  until  a  distinct  yellow  tint  is  obtained. 


FIG.  316. 


NEGATIVE- MA  KING  —  DRY. 


337 


out,  after  digestion,  into  a  tall,  square  glass  bottle,  which  should  not  be  more 
than  a  quarter  full  at  the  most.  The  bottle  is  then  laid  on  its  side,  and  the 
emulsion  allowed  to  set.  When  it  has  set,  the  bottle  is  filled  completely  with 
water,  tightly  corked,  and  laid  on  its  side  so  that  the  part  covered  with  emul- 
sion is  uppermost.  The  water  should  be  changed  repeatedly  during  twenty- 
four  hours,  after  which  the  emulsion  is  ready  for  coating ;  about  an  ounce  of 
alcohol  should  be  added  previously,  and,  if  the  emulsion  is  to  be  kept,  an  anti- 
septic may  be  added." 

159.  Armed  now  with  a  stock  of  clean  plates,  slightly  warmed,  and  a  quan- 

2  drachms  50  minims  (10  c.cm.)  of  the  silver  solution  are  then  added,  which  change  the 
color  to  clear  reddish-yellow  or  deep  red  if  the  emulsion  has  been  sufficiently  washed. 
Very  well  washed  emulsions  strike  the  red  color  with  85  minims  of  the  silver  solution, 
and  then  contain  less  than  0.05-0.06  per  cent,  of  soluble  bromide.  But  if  340  minims 
of  the  silver  solution  strike  no  red  color,  or  even  no  change  of  color  at  all,  it  is  proof  of 
insufficient  washing. 

This  test  can  only  be  used  with  neutral  aqueous  emulsions.     Those  containing  acetic 
acid  must  first  have  it  removed  or  neutralized. 

The  whole  analysis  may  be  made  by  daylight,  though  candle-  or  gaslight  will  also 
enable  the  change  of  color  to  be  distinctly  seen. 

A  trouble  with  all  forms  of  washing  apparatus  is  that  the  pores  of  the  muslin  used  for 
straining  soon  get  stopped  up.  The  pressing  canvas  should  be  thrown  into  hot  distilled 
water  immediately  after  use,  well  kneaded  about,  and  then  rinsed  three  times  in  hot 
water  until  there  is  no  further  milkiness.  This  is  best  done  in  the  dark,  for  the  light 
soon  turns  the  stuff  brown,  and  it  can  only  be  bleached  again  with  weak  acid  (1  part 
nitric  acid,  100  parts  water).  All  the  cloths  used  for  filtering  are 
cleaned  in  the  same  way.— DR.  H.  W.  VOGEL.  FIG.  317. 

All  foreign  matter  should  be  removed  by  filtering  through  thick  cot- 
ton cloth  or  washed  cotton  fitted  into  a  funnel.  But  the  funnel  must 
be  kept  warm  so  as  not  to  allow  the  gelatine  to  set.  Special  arrange- 
ments for  this  purpose,  such  as  a  metal  case  carrying  hot  water  and 
applied  around  the  funnel,  are  very  convenient.  The  emulsion  will 
soon  choke  the  filter;  this  must  be  helped  out  by  occasionally  working 
the  cloth  gently  to  and  fro.  =  . 

Braun's  pneumatic  filters  have  lately  come  much  into  favor.  They 
consist  of  a  glass  balloon  tied  over  with  chamois-skin  below,  and 
fitted  above  with  a  valve  and  rubber  pumping  ball.  The  opening  in 
the  neck  having  been  uncovered,  and  the  emulsion  poured  into  the 
previously  warmed  balloon,  the  filtration  goes  on  by  pressing  the  ball 
(the  cap  fitting  on  the  opening,  of  course,  being  replaced.  Fig.  317)  • 
—DR.  H.  W.  VOGEL. 

159.  Spontaneous  drying  will  answer  in  a  clear,  dark  room,  the  time  required  being 
regulated  by  the  changing  dampness  of  the  air.     In  damp  winter  weather  the  drying  will 

22 


338 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  318. 


tity  of  emulsion  from  which  we  may  expect  everything,  we  proceed  to  the  dark 
room  to  unite  them.  The  emulsion  is  poured  upon  the  plate  in  the  same 
manner  as  the  collodion,  from  a  warmed  measure.  A  glass  rod  is  used  to 
insure  an  even  coating,  and  the  superfluous  emulsion  is  persuaded  from  one 

• 

often  occupy  three  days,  and  there  is  risk  of  those  spots  remaining  wet  the  longest  be- 
coming decomposed.  In  such  cases  efforts  must  be  made  to  hasten  the  drying.  This 
may  be  done  on  the  small  scale  by  immersing  the  (set)  plate  in  alcohol  for  five  minutes; 
this  removes  the  greater  part  of  the  water,  so  that  the  plates  will  often  dry  in  one  or  two 
hours.  But  this  is  too  costly  to  be  practised  extensively.  An  artificial  draft  is  gener- 
ally used  in  such  cases. 

For  small  batches  of  plates,  my  form  of  drying-box  may  be  used.  It  has  proved 
very  serviceable,  and  may  be  constructed  at  a  moderate  cost.  It  is  made  of  tin,  and  is 

shown  in  the  figure  in  section.  Tis  the  door  opening 
at  two  corners,  and  shutting  light-tight,  with  over- 
hanging edges ;  a  a  are  shelves  of  tin  soldered  fast  to 
the  sides.  They  are  so  arranged  that  the  air  circu- 
lates in  the  direction  shown  by  the  arrows.  On  these 
shelves  the  plates  are  laid  after  being  firmly  set.  The 
air  gains  access  through  the  tube  u  under  the  lowest 
shelf,  and  in  order  to  create  the  necessary  draft,  a 
chimney,  /SJ  which  consists  of  two  riveted  parts  fitting 
by  a  joint,  and  thirty-nine  inches  high,  is  fitted  at  the 
top  of  the  box.  A  gas-flame,/,  burns  inside  the  chim- 
ney as  seen  in  the  figure,  g  being  the  supply-pipe.  As 
soon  as  the  flame  is  lighted,  a  strong  draft  is  formed  in 
the  chimney  which  sucks  air  through  the  box,  and 
causes  the  plates  to  dry  as  quickly  as  they  would  in  a 
well- ventilated  room.  If  the  weather  is  clamp,  and  it 
is  wished  to  hasten  the  drying,  a  pan  of  fused  chloride 
of  calcium  is  set  at  the  bottom  of  the  box.  It  is  well 
to  arrange  a  piece  of  tin  under  the  flame  to  serve  as  a 
cut-off  for  the  light,  and  prevent  its  entering  the  box. 
The  piece  b  also  is*  painted  with  dead-black  varnish, 
as  well  as  the  lower  surface  of  the  upper  wall  of  the  box.  Of  course,  the  door  T  must 
fit  tightly  to  the  edges  a  a,  otherwise  the  air  would  rise  perpendicularly,  and  not  circu- 
late over  the  plates.  A  layer  of  felt  is  fitted  to  the  door  so  as  to  effect  this.  In  a  box 
of  this  kind,  constructed  for  7  x  9  inch  plates,  the  author  dried  eight  dozen  plates. 

Large  wooden  drying-boxes  have  been  made  on  the  same  plan.  The  higher  the 
chimney  and  the  larger  the  flame,  the  more  powerful  the  draft.  For  such  boxes  several 
air-openings  will  be  necessary,  but  care  must  be  taken  that  the  air  admitted  is  free  from 
dust. 

The  manufacturers  have  drying-rooms,  well  protected  from  light,  and  with  a  current 
of  air  from  a  ventilating  machine  driven  by  steam-power  or  gas. 


NEGATIVE -MAKING  —  DRY. 


339 


corner  into  a  bottle.  The  plate  is  then  placed  on  a  level  shelf,  and  there  left 
to  set.  From  this  it  is  removed  to  a  drying  cupboard,  and  still  levelled, 
there  retained  at  an  even  temperature  until  quite  dry.  This  operation  should 
not  be  hastened.  Alcohol  may  be  used  in  an  emergency  to  facilitate  drying. 

Warm  air  is  frequently  admitted  to  the  drying-box.  The  chimney  S,  for  instance, 
may  be  surrounded  with  a  metal  case,  and  the  heated  air  generated  in  the  space  between 
them  conducted  to  the  opening  u  by  means  of  a  tube;  care  must  be  taken,  however,  not 
to  let  the  temperature  rise  above  76°  F.  I  prefer  air  at  ordinary  temperatures.  It  is 
important  that  the  drying  proceed  evenly,  for  at  every  point  of  the  film  where  a  check 
in  the  evaporation  occurs,  a  streak  is  sure  to  form. — DR.  H.  W.  VOGEL. 

Mons.  Harrison,  Jr.,  presented  the  French  Photographic  Society  with  the  model  of  a 
drying  chamber  for  drying  carbon  tissue,  gelatine  emulsion  and  dry  plates. 

Fig.  319  presents  a  side  view  of  the  apparatus.  No.  1  is  a  sheet-iron  bottom  heated 
by  a  spirit  or  gas  lamp ;  the  cold  air  enters  by  No.  2,  and  passing  over  the  hot  plate,  is 
heated,  and  follows  the  direction  of  the  arrow  until  it  makes  its  exit  by  the  chimney  at 
No.  3.  * 


FIG.  319. 


FIG.  320. 


FIG.  321. 


In  Fig.  320  the  front  of  the  apparatus  is  seen 
A,B,  C.  D,  are  the  shelves  upon  which  the  objects 
to  be  dried  are  laid.  The  door  No.  3  is  closed ;  this  door  pressing  against  the  shelf  B, 
closes  the  communication,  and  compels  the  air  to  take  the  direction  of  the  arrows,  as  seen 
in  Fig.  319.  The  value  of  this  apparatus  needs  no  further  comment. 

I  draw  your  attention  to  a  new  stand,  or  plate-holder,  which  has  for  its  object  the  rapid 
drying  of  gelatin  plates.  Some  operators  propose  ovens  and  others  drying  apparatus, 
either  by  heat  or  a  current  of  air ;  others  prefer  spontaneous  desiccation.  I  find  the 
latter  preferable  with  a  slight  modification.  As  soon  as  I  have  covered  my  plate  I  lay 
it  on  a  perfectly  levelled  sheet  of  patent  glass,  which  is  kept  cold  by  a  stream  of  cold 
water  running  under  it.  As  soon  as  the  gelatine  emulsion  has  set  I  take  it  up,  and 
insert  it  into  the  rack  shown  by  Fig.  321.  This  rack  or  plate-stand  is  easily  made.  A  is  a 


340        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

160.  The  exposure  of  emulsion  plates,  owing  to  their  increased  sensitiveness, 
should  be  made  with  careful  study  of  all  the  attendant  circumstances.     The 
almost  morbid  desire  for  instantaneity,  now  existing  to  a  far  too  great  degree, 
causes  many  failures.     There  is  no  advantage  in  quick  exposures  for  general 
subjects.     In  fact,  there  is  oftentimes  decided  disadvantage.     Take  into  con- 
sideration everything  and  use  "  lightning  plates "  only  when  their  power  is 
absolutely  required.     For  ordinary  work '  go  slower,  and  take  your  compen- 
sation in  better  results.     When  you  are  a  master  in  precision,  then  you  may 
use  the  hair-trigger  and  expect  to  hit  the  glass  ball  almost  every  time.     Until 
exposure  becomes  an  inspiration  with  you,  think  caremlly  every  time.     Of 
course  there  are  times  when  one  must  take  the  risk  and  throw  rules  aside. 
Accidental  pictures  are  sometimes  very  fine.     The  remarks  on  exposure  in 
another  chapter  should  be  regarded. 

161.  The  development  of  a  gelatine  plate  is  no  less  beautiful  than  the 

piece  of  wood  into  which  is  glued  the  support,  J3,  and  the  two  legs,  C  C/.  The  support, 
B,  holds  one  dozen  pegs,  which  slide  up  and'  down  with  ease.  A  spring,  E,  is  put  on 
each  peg,  in  order  to  keep  it  down.  On  the  two  legs,  C  C',  are  twelve  notches  correspon- 
ding to  the  twelve  pegs.  The  apparatus  is  hung  up  against  the  wall  of  the  drying-room 
by  means  of  the  hook,  F.  As  soon  as  the  film  of  gelatine  has  set,  the  plate  is  taken,  and 
one  of  its  corners  is  inserted  into  a  hole  at  the  bottom  of  peg  No.  1 ;  a  little  for.ce  is  used 
to  push  up  the  spring,  and  the  plate  is  then  put  into  the  notches ;  this  spring  now  pushes 
down  the  peg,  and  the  plate  is  firmly  held.  The  same  movement  is  repeated  for  the 
twelve  plates,  and  the  rack  is  hung  up  for  them  to  dry,  which  is  easy,  as  there  is  the 
space  of  an  inch  between  each  plate. — PROF.  E.  STEBBING. 

160.  Local  Strengthening  during  Development. — This  is  the  method  adopted   for  the 
development  of  interiors,  or,  when  it  is  necessary,  to  bring  out  the  thick  shadows  of  trees, 
especially  in  the  case  of  under-exposure.     In  an  alkaline  bath  the  developer  is  allowed 
to  act;  a  solution  of  ammonia,  rather  stronger  than  that  for  the  development,  is  used  for 
touching  the  undeveloped  parts  of  the  plate,  care  being  taken  to  keep  the  brush  in  motion, 
and  dipping  it  from  time  to  time  in  the  ammonia.     By  this  means  it  is  possible  to  bring 
out  details  which,  under  ordinary  circumstances,  are  lost.    The  same  process  may  be 
applied  to  an  over-exposed  plate,  by  using  pyrogallic  acid  instead  of  ammonia. — J.  H.  F. 
ELLERBECK. 

161.  It  is  a  mistake  to  judge  of  dry-plate  negatives  as  you  would  wet  plates ;  they  are 
totally  different,  and  it  is  those  negatives  which  are  most  like  a  wet  plate  in  appearance 
which  disappoint  you  in  the  printing.    This  it  is  which  makes  it  so  difficult  for  a  photog- 
rapher, using  both  processes,  to  make  even  work,  and  it  also  tends  to  confirm  him  in  the 
opinion  that  he  cannot  produce  such  good  work  with  the  dry  process  as  he  can  by  the 
wet,  because  he  judges  his  dry  negatives  by  a  wet  standard,  and  tries  to  get  them  as  near 
a  wet  plate  in  appearance  as  possible,  and  the  nearer  he  succeeds  in  this  the  more  disap- 
pointed he  will  be  with  the  resulting  prints. 


NEGATIVE-MAKING  —  DRY.  341 

moulding  of  the  clay  into  form  by  the  sculptor.     With  the  knowledge  how 
to  mix  his  potent  chemicals,  and  with  a  mind  that  directs  carefully,  the  pho- 

All  the  negatives  which  produce  the  best  prints  here  are  quite  unlike  a  wet  plate — in 
fact,  judging  from  his  standard,  the  wet  plate  operator  would  doubtless  pronounce  them 
overexposed  and  flat.  The  shadows  are  not  so  clear  as  they  must  be  in  a  wet  plate  to 
produce  a  brilliant  print,  and  the  highest  lights  are  anything  but  opaque,  but  they 
produce  a  print  which  is  at  the  same  time  soft  and  brilliant,  full  of  gradation,  and  yet 
with  a  snap  that  is  seldom  seen  in  a  wet  plate  which  has  no  such  soft  delicate  demitints. 

I  think  that  every  dry-plate  maker  gives  in  his  formula  for  development  the  fullest 
amount  his  plate  will  stand  of  the  accelerator,  and  I  find  it  best  to  give  exposure  enough 
to  enable  me  to  use  less  of  the  accelerator  than  the  formula  given  with  the  plates.  I  am 
quite  sure  that  I  get  better  results  than  by  a  shorter  exposure  and  full  strength  of  normal 
developer  given  by  the  platemaker ;  of  course,  there  are  subjects  which  must  be  macfe  as 
rapidly  as  possible,  such  as  street  views  and  drop  shutter  exposures.  The  way  I  treat  a 
plate  which  has  had  an  exposure  of  a  fraction  of  a  second,  or  any  underexposed  plate, 
is  this :  when  I  find  that  under  the  normal  development  it  is  coming  up  slowly  and  the 
highest  lights  are  gaining  too  much  intensity  while  the  shadows  remain  unseen,  I  put 
in  a  large  amount  of  water,  sometimes  as  much  as  four  times  the  amount  the  develop- 
ment was  commenced  with ;  for  instance,  I  develop  a  10  x  12  plate  with  four  ounces  of 
water,  to  which  have  been  added  two  drachms  each  of  pyro  and  potash  solutions  (normal 
developer).  On  finding  that  the  plate  has  not  received  enough  exposure,  I  put  in  four, 
eight,  or  twelve  ounces  of  water,  and  increase  the  accelerator  till  I  have  had  as  much  as 
twelve  drachms  of  accelerator  to  two  drachms  of  pyro  in  sixteen  ounces  of  water.  To 
prevent  frilling  I  use  chrome  alum.  The  progress  of  development  is  slow,  but  sure. — 
GEO.  HANMER  CROUGHTON. 

The  whys  and  wherefores  of  failure  are  not  so  far  to  seek  but  that  they  can  be  found 
on  the  same  day.  Some  of  the  developers  are  chemical  curiosities,  or  would  be,  if  any 
man  could  ever  get  the  mess  to  stay  in  solution.  The  solutions  of  "pyro"  are,  indeed, 
fearfully  and  wonderfully  made,  but  with  a  pertinacity  worthy  of  emulation,  it  refuses 
to  amalgamate,  dissolve,  stay  so,  and  if  the  "immature"  commences  all  right,  and  does 
not  guess  at  his  exposure,  he  gets  a  fair  negative  or  two,  and  in  a  week  or  so  after  he 
"  drops"  on  some  view  and  goes  home  to  behold  a  charming  example  of  a  thin  negative, 
never  dreaming  that  his  pyro  compound  solution,  minus  bromide  of  brains,  is  as  uncer- 
tain as  a  saturated  solution  of  anything  made  up  from  two  different  lots  of  chemicals. 
Having  made  his  exposure,  and  supposed  it  is  normal,  he  proceeds  to  mix  a  "  normal 
developer"  see  circular.  The  image  commences  to  come  "too  fast;  he  slaps  in  plenty 
of  bromide,  and  it  calls  a  halt,  and  he  gets  an  uncertain  amount  of  density,  a  marvellous 
lack  of  detail,  and  a  most  beautiful  and  conspicuously  charming  lack  of  harmony  or 
gradation.  The  developer  is  then  poured  down  the  spout  and  a  new  one  made  up  for 
the  other  plate.  Having  profited  by  his  experience(?)  he  now  commences  with  less  pyro 
and  alkali,  and  all  comes  up  pretty  well.  But  somehow  it  now  commences  to  drag,  and 
when  it  has  come  to  a  certain  point  it  refuses  to  get  denser,  or  to  give  out  the  detail. 
More  pyro,  and  it  gets  worse  ;  more  soda;  and  it  looks  better ;  and  finally  it  goes  through 


342        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

tographer  has  power  at  hand  which,  with  the  exercise  of  the  art  and  science  in 
him,  may  produce  wondrous  results.  The  number  of  changes  he  may  cause  is 

the  alum  and  hypo,  and  comes  out  a  ghost — past  all  patching,  and  our  "  immature  " 
worker  then  goes  for  the  platemaker  more  vigorously  than  politely. 

We  have  solutions  which  contain  quite  too  much  alkali,  and  sometimes,  if  we  follow 
the  exact  formula,  we  find  a  superabundance  of  material  which  lies  harmlessly  in  the 
bottom  of  the  bottle,  undissolved  and  useless.  Some  of  the  pyro  solutions  are  charming 
instances  of  chemical  ignorance,  if  not  comical  in  their  effects,  and  many  of  our  plate- 
makers  seem  to  ignore  the  fact  that  pyro  cannot  be  kept  in  any  solution,  so  far  as  is  yet 
known,  and  retain  its  power  to  develop ;  and  if  it  could  do  so,  bromide  of  any  kind 
should  not  be  added  to  pyro  solution.  If  the  most  perfect  results  are  desired  or  expected, 
andjf  the  positively  best  results  are  desired,  then  no  bromide  of  any  kind  should  be  put 
in  the  developer  in  any  form.  But  it  is  so  exceedingly  difficult  to  give  exactly  the 
correct  exposure  that  some  bromide  is  necessary;  and  a  better  way  is  to  dilute  your 
developer  slightly,  and  make  use  of  a  little  more  time  in  development,  gaining  density 
not  at  the  expense  of  detail  or  harmony. — THOS.  PRAY,  JR. 

Go  Slow :  The  demand  for  extra  rapid  plates  that  will  develop  without  the  use  of  a 
restrainer  is  so  great  that  a  really  good  plate  is  often  condemned  because  it  does  not  give 
the  results  it  would  have  given  had  a  restrainer  been  used.  To  me  it  is  the  same  as  to 
try  to  use  the  protosulphate  of  iron  developer  without  using  acetic  acid ;  for  both  plates 
negatives  have  been  obtained  without  its  use,  and  with  very  short  exposures,  but  they 
had  very  little  printing  qualities.  In  a  prominent  gallery  here  1  saw  a  favorite  plate 
developed,  and  the  user  praised  it  highly.  No  bromide  or  citric  (pyro,  sulphite,  and 
soda  was  the  developer).  The  negative  seemed  perfection.  Calling  at  the  same  place 
at  another  time,  saw  plates  developed  (pyro,  bromide,  and  ammonia  developer).  "  Is 
this  the  plate  you  used  when  I  was  here  before!"  "Oh,  no ;  this  is  an  English,  Birming- 
ham, England,  plate."  "Why,  I  thought  you  liked  the  other  plate  so  well?"  "So  I 
did  ;  but  they  do  not  always  come  the  same — thin,  no  body.  Now,  these  Birmingham 
ones  are  so  round  and  full  of  detail."  I  firmly  believe  that  had  the  pyro,  sulphite,  and 
soda  been  used  with  a  restrainer,  and  a  trifle  more  time  given,  that  the  favorite  plate 
would  have  been  as  round  and  full  of  detail  as  the  foreign  plate. 

I  have  been  led  to  these  remarks,  as  I  have  devoted  time  and  money  to  endeavor  to 
make  emulsions  of  uniform  quality  and  developable  with  any  published  formula  that 
photographers  are  more  conversant  with,  but  very  seldom  with  the  developer  without  a 
restrainer,  and  I  judge  that  the  prominent  manufacturers  of  the  country  will  coincide 
with  me,  viz.,  that  all  plates  can  be  developed  with  ferrous  oxalate,  bromide,  and  citric 
acid  restrainer,  but  not  always  with  pyro,  no  matter  what  alkali  be  used  unrestrained. — 
WM.  BELL. 

A  preliminary  bath  (Vorbad).— Mr.  Jastrzembsky  recently  published  an  interesting 
expedient  for  increasing  the  sensitiveness  of  a  gelatine  plate.  He  immerses  the  plate  a 
minute  or  two  in  a  solution  of  carbonate  of  sodium  1 : 100,  and  dries.  I  tried  the  method, 
and  found  it  to  work  admirably.  He  remarks  quite  truly,  that  the  treatment  with  a 
solution  of  sodium  carbonate  increases  the  tendency  to  frilling,  and  that,  therefore,  a 
substratum  becomes  necessary. — DR.  H.  W.  VOGEL. 


NEGATIVE-MAKING  —  DBY.  343 

infinite.     A  turning  of  the  wrist,  a  thoughtless  movement  of  the  hand,  a  few 
drops  in  excess,  or  stinting  the  solution  here  and  there,  may  alter  the  form  and 

Accelerator  for  Development. — For  some  time  past  the  preliminary  bath  (Vorbad)  has 
been  playing  a  rather  practically  important  part  in  photography.  In  development  it 
has  come  into  service.  It  is  well  known  that  underexposed  plates  give  very  strong  con- 
trasts in  light  and  shade,  the  high  lights  becoming  very  intense  before  the  shadows  show 
any  detail,  the  more  delicate  parts  being  lost.  These  defects  may  be  avoided  by  im- 
mersing the  plate,  before  development,  in  a  bath  of  1  part  hypo  to  5000  parts  water,  then 
using  the  ferrous  oxalate  as  a  developer.  The  image  quickly  appears,  the  high  lights 
are  not  so  intense  and  the  time  of  development  is  reduced  one-third.  The  same  effect 
is  not  had  with  the  pyro  developer.  Recently  besides  hypo  other  bodies  have  been  used 
which  accomplish  the  same  result.  To  these  belong  especially  Lohse's  preliminary 
bath,  recommended  by  Dr.  Messerschmidt,  consisting  of  a  solution  of  nitrate  of  chrys- 
aniline  1 :  20,000.  According  to  the  experiments,  this  bath  worked  very  energetically, 
even  more  so  than  the  hypo,  without  the  disadvantage  which  the  latter  sometimes  occa- 
sions, the  formation  of  a  fog.  Mr.  Quidde  has  also  used  the  chrysaniline  with  excellent 
results.  He  is  also  convinced  that  the  action  is  more  energetic  than  the  hypo.  He 
employed,  at  first,  a  solution  of  1  part  in  3000  of  water,  later  making  the  dilution  1 :  20,000, 
but  no  apparent  difference  in  the  action  of  the  two  baths  could  be  perceived.  One  thing 
was  sure,  there  was  no  appearance  of  any  fog,  but  he  did  observe  in  all  his  experiments 
numerous  small  specks  on  the  plate;  on  examination  he  found  that  the  chrysaniline  had 
not  been  thoroughly  dissolved,  hence  the  small,  undissolved  particles  were  the  cause  of 
the  specks  on  the  plate.  After  filtering  the  solution,  the  specks  entirely  disappeared. — 
DR.  H.  W.  VOGEL. 

Handling  the  Developer. — I  never  pour  developer  on  a  dry  plate,  but  prefer  placing  the 
plate  in  the  solution,  and  using  very  little  motion  of  the  solution  while  developing.  And 
that  gives  me  time  to  do  other  things ;  while  if  I  wish  .to  step  out  of  the  dark-room,  I 
place  a  board  over  the  developing  dish.  I  have  no  difficulty  or  trouble.  I  never  inten- 
sify or  reduce,  as  either,  in  my  opinion,  spoils  the  negative  in  a  few  months. 

Don't  expect  the  development  to  be  too  rapid;  one  second  exposure  on  a  child  is 
enough.  Though  the  negative,  looks  thin,  it  will  print  much  stronger  than  you  had  the 
least  idea  of.  Keep  your  hand  off  the  back  of  the  plate  at  all  times.  Brush  every  plate 
off  well  before  placing  in  the  holder.  Save  and  filter  all  your  old  developer,  to  prepare 
your  negatives  for  final  development  with  new.  Don't  add  all  your  iron  to  the  developer 
at  once,  as  you  can  add  the  balance  if  needed,  but  can't  take  it  out  if  too  much.  Usually 
half  the  quantity  of  iron  will  do,  if  using  oxalate  developer.  Pl&ce  your  plate  carefully 
in  the  holder,  and  pull  out  the  slide  easily,  without-  any  jar  (having  covered  the  instru- 
ment and  holder  with  your  common  cloth) ;  put  in  the  slide  square,  and  not  one  corner 
first;  and  let  simple  sense  follow  "simple  thing,"  and  you  must  succeed. — O.  PIERRE 
HAVENS. 

What  developer  shall  we  use  ?  The  ammonia  is  the  nearest  in  point  of  time  and  action 
to  the  wet  process,  but  it  is  such  uncertain  working,  no  two  days  alike.  To-day  we  can 
work,  say,  three  minims  to  the  ounce  of  developer  with  fair  results ;  perhaps  to-morrow 
it  may  demand  five ;  then  look  out  for  foggy  times.  Then  we  take  the  carbonate  of 


344        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

nature  of  the  image  as  much  as  the  careless  pressure  and  unskilled  turning  of 
the  clay  by  the  sculptor  may  ruin  the  loveliness  of  the  statue. 

Two  methods  of  development  with  their  modifications  find  about  equal  use 

soda,  which  appears  to  have  the  least  amount  of  latitude  of  variation  of  exposure.  If 
you  sin  on  either  side,  what  is  the  outcome  ?  If  it  is  on  the  good  old  side  of  time  enough 
and  to  spare,  then  you  must  add  the  restrainer,  and  get  the  blessing  of  the  printer  on 
your  devoted  head ;  or  if  you  make  sure  to  keep  under  the  limits,  you  feel  disgusted  with 
yourself.  But  here  comes  a  compromise  which,  with  a  watchful  eye,  will  relieve  us  of 
some  of  our  trouble : 

A.  Water,  12  ounces ;  citric  acid,  60  grains  ;  pyro,  I  ounce ;  sulphite  of  soda,  2  ounces. 

B.  Water,  12  ounces;  carbonate  of  potash,  1J  ounces  ;  sulphite  of  soda,  3  ounces. 
Now  here  we  have  a  stock  solution  that  contains  all  that  can  be  desired  for  a  great 

variety  of  work. 

For  rapid  exposures  take  of  the  pyro  solution,  1  drachm  ;  water,  2  ounces  ;  carbonate 
of  soda,  1  drachm.  But  if  you  find  the  image  coming  too  rapidly,  add  a  few  drops  of 
bromide  solution,  being  careful  to  keep  the  plate  gently  in  motion.  If  it  is  left  to  stand 
quietly  for  any  time  it  will  produce  a  mottling  of  the  plates. 

Now,  after  you  have  developed  the  first  plate  you  see  the  action,  and  if  it  is  too  rapid 
use  less  of  the  carbonate  solution ;  if  you  wish  more  density,  increase  the  quantity  of 
pyro  solution,  or  if  the  same  class  of  negatives  with  less  density  add  more  water. 

I  find  this  to  be  the  best  in  use,  as  there  is  no  need  of  fogging  any  plate  from  develop- 
ment. It  has  helped  me  many  times  in  developing  plates  exposed  by  others.  When  I 
have  no  knowledge  of  the  sensitiveness  of  any  brand  of  dry  plates  my  plan  is  to  make  a 
solution  about  one-fourth  the  usual  strength,  then  the  action  is  so  slow  that  it  will  give 
one  time  to  calculate  the  strength  of  the  developer  required. 

If  it  should  come  up  with  an  overtimed  appearance,  then  use  in  the  regular  developed 
a  few  drops  of  the  bromide  and  less  of  the  carbonate.  If  the  shadows  show  evidence  of 
being  undertimed,  the  regular  developer  comes  in  play. 

After  fixing  most  photographers  immerse  the  negative  in  an  alum  solution,  which  is 
good,  as  it  hardens  the  film  and,  in  many  cases,  gives  the  negative  a  pleasant  (to  an  old 
wet  worker)  gray  tone.  Should  this  not  give  you  the  color  you  desire  try  after  taking 
from  the  fixing  bath,  a  flow  or  two  of  the  regular  wet-plate  developer.  It  will  save  you 
a  few  hours  in  these  short  days  in  printing. — GEO.  ENNIS. 

Pyro  and  Carbonate  of  Potassa  Developer.  A  modification  of  Dr.  Stolze's  and  Dr.  Eder's 
Formula.  Stock  solutign  No.  1 :  Citric  acid,  60  grains ;  pulverize  and  dissolve  in  dis- 
tilled or  ice  water,  8  ounces ;  granular  sulphite  of  soda,  1  £  ounce ;  pyrogallic  acid,  1 
ounce.  Stock  solution  No.  2 :  Pure  ice  or  distilled  water,  8  ounces ;  carbonate  of  potassa, 
pure,  3  ounces. 

The  sulphite  of  soda,  carbonate  of  potassa,  and  both  stock  solutions  should  be  kept  in 
well-stoppered  bottles,  glass  stoppers  are  preferable  for  the  carbonate  of  potassa.  The 
latter  should  be  completely  soluble  in  the  given  quantity  of  water,  if  sufficiently  pure. 

Developer:  Stock  solution  No.  1,  £  ounce;  Stock  solution  No.  2,  £  ounce;  water,  12 
ounces. 


NEGATIVE-MAKING  —  DRY.  345 

among  photographers.  The  first  method  is  the  alkaline,  in  which  pyrogallic 
acid,  bromide,  and  ammonia  are  the  chief  features ;  and  the  other  is  the  ferrous 
oxalate  combination.  A  few  advocate  the  use  of  two  solutions. 

The  developer  should  be  used  within  a  couple  of  hours  after  mixing,  as  it  will  work 
slower  and  produce  yellow  negatives  when  old. 

This  developer  is  very  powerful,  and  can  be  worked  with  one-half  the  exposure  re- 
quired by  many  other  developers  in  use. 

If  the  plate  was  overexposed,  the  detail  in  the  shadows  will  appear  too  soon,  and  will 
be  all  developed  before  the  lights  have  gained  sufficient  intensity,  the  resulting  negative 
being  flat  and  without  sufficient  contrast.  As  soon  as  you  notice  in  developing  that  the 
plate  has  been  over-exposed,  add  immediately  to  each  four  ounces  of  developer,  one 
drachm  of  bromide  solution  (one  ounce  of  bromide  of  ammonium,  twenty  ounces  of 
water),  which  will  produce  more  intensity  and  will  save  the  negative. 

If  the  plate  was  underexposed,  the  detail  in  the  shadows  will  not  appear  in  time  and 
the  negative,  if  fully  developed,  will  be  too  strong  in  the  lights  and  deficient  in  detail  in 
the  shadows.  In  this  case  the  negative  may  be  improved  by  adding  to  the  developer  in 
the  dish  three  times  its  bulk  of  cold  water  ;  move  the  dish  to  insure  a  good  mixing,  cover 
it  and  allow  to  stand  quietly,  giving  plenty  of  time  for  the  development  of  the  detail, 
which  will  come  provided  the  exposure  has  not  been  entirely  too  short. — G.  CRAMER. 

This  is  my  latest  method : 

No.  1.  Pyro-solution :  Distilled  or  ice  water,  10  oz.;  sulphite  of  soda  crystals,  4  oz., 
dissolve  and  add  slowly;  sulphuric  acid,  1  drachm;  pyrogallic  acid,  Schering's,  1  oz. ; 
and  water  to  make  16  ounces  fluid. 

No.  2.  Alkaline  solution :  Water,  10  oz. ;  granulated  carbonate  of  potash,  2  oz. ;  granu- 
lated carbonate  of  soda,  2  oz. ;  dissolve,  add  water  to  make  measure  16  ounces. 

Bromide  solution :  Bromide  potass.  1  part ;  water,  9  parts. 

To  develop.  For  portraits  on  "special  instantaneous,"  to  4  ounces  of  water  add  3 
drachms  No.  1  and  2  drachms  No.  2,  and  if  the  plate  has  had  proper  exposure,  the  above 
developer  will  be  found  to  yield  a  soft  and  rich  printing  negative.  More  of  No.  2  to  be 
added  if  under-exposed,  and  more  of  No.  1  with  a  few  drops  of  bromide  solution  if  over- 
exposed. 

For  landscapes  and  interiors  on  "specials,"  where  the  exposure  may  be  uncertain,  lay 
the  exposed  plate  in  the  pyro  solution  for  a  minute  or  two,  then  into  the  developing 
glass  put  half  the  quantity  of  No.  2  as  has  been  taken  of  No.  1,  and  pour  the  pyro  solu- 
tion into  it,  and  back  on  to  the  plate ;  by  proceeding  in  this  manner,  adding  more  of  No. 
2  to  bring  out  the  image,  or  a  few  drops  of  a  10  per  cent,  solution  of  bromide  to  restrain, 
as  may  be  required,  much  better  results  may  be  looked  for  than  if  a  full  quantity  of  No. 
1  and  No.  2  were  mixed  at  once.  For  instantaneous  views,  or  very  dark  interiors,  I 
recommend  the  following  procedure :  To  4  ounces  water  add  1  drachm  No.  2,  soak  plate 
in  this  while  preparing  the  following:  water,  3  ounces;  of  Nos.  1  and  2  each  3  drachms; 
5  drops  bromide  solution;  pour  off  the  dilute  alkali,  and  flow  this  strong  developer  over 
the  plate;  be  careful  to  expose  the  plate  as  little  as  possible  to  the  light  used  to  develop 
by,  no  matter  how  safe  it  may  be  considered  for  ordinary  development.  Do  not  hurry 


346        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Those  who  use  commercial  dry  plates  should  develop  them  as  instructed  by 
their  manufacturer.  The  modifications  offered  by  practical  workers  would  fill 
a  volume. 

by  adding  more  No.  2;  cover  up  the  pan  and  give  the  developer  time  to  act,  when  more 
of  No.  1  or  No.  2  may  may  be  added  as  may  be  required.  For  instantaneous  marine 
views,  it  will  be  best  to  treat  the  plate  the  same  as  for  landscapes,  by  soaking  the  plate 
in  the  pyro  solution  first. 

For  landscapes,  machinery,  architecture,  etc.,  on  B  plates  use  ?  drachm  each  Nos.  1 
and  2  to  each  ounce  water,  adding  more  of  each  as  may  be  required,  No.  1  giving  density, 
No.  2  giving  detail  and  hastening  development.  After  washing  off  developer,  immerse 
in  following  hardening  and  clearing  solution :  Water,  36  oz. ;  chrome  alum,  J  oz. ;  citric 
acid,  J  oz.,  3  to  5  minutes;  then  wash  and  place  in  the  fixing  solution:  hyposulphite  of 
soda,  8  oz. ;  water,  40  oz.  Let  remain  a  few  minutes  in  the  hypo  solution  after  all 
bromide  of  silver  appears  to  be  dissolved  out,  then  wash  in  running  water  for  not  less 
than  one  hour,  swab  off  the  film  with  a  tuft  of  cotton,  while  water  runs  over  it,  then  place 
away  to  dry  spontaneously. 

Temperature  of  development  has  a  great  influence  on  the  result.  It  should  be  kept  if 
possible  within  a  change  of  ten  degrees ;  between  60°  and  70°  F,  is  a  good  temperature 
to  secure  uniform  results.  Cold  retards  development,  heat  accelerates,  and  causes  flat- 
ness, therefore  in  summer  time  less  No.  2  solution  should  be  used,  and  in  winter  equal 
parts  of  Nos.  1  and  2  will  be  found  about  right. 

Over-exposure,  if  known  or  suspected,  commence  development  as  directed  under  the 
head  of  landscapes  and  interiors.  . 

Under-exposure  can  be  remedied  in  a  certain  degree,  but  not  entirely,  by  first  soaking 
plate  in  water  to  which  has  been  added  1  drachm  No.  2  to  4  oz.  water,  then  use  developer 
composed  of  half  drachm  each  Nos.  1  and  2  to  1  oz.  water,  and  continue  development 
slowly ;  but  the  best  remedy,  when  possible  to  adopt  it,  is  to  expose  another  plate,  giving 
longer  exposure. 

In  very  hot  weather,  I  recommend  the  use  of  the  alum  bath  before  fixing,  and  always 
afterwards. 

Intensification.  With  correct  exposure  and  development,  intensification  need  never 
be  resorted  to.  The  following  formula  is,  however,  very  effective : 

No.  1.  Bichloride  of  mercury,  240  grains ;  chloride  of  ammonium,  240  grains;  distilled 
water,  20  ounces. 

No.  2.  Chloride  of  ammonium,  480  grains ;  water,  20  ounces. 

No.  3.  Cyanide  potass,  (refined),  120  grains;  water,  16  ounces;  nitrate  of  silver,  100 
grains ;  water,  4  ounces. 

Add  the  solution  of  silver  to  the  solution  of  cyanide,  until  a  slight  precipitate  remains 
undissolved. 

Let  the  plate  to  be  intensified  wash  for  at  least  half  an  hour,  then  lay  in  alum  solution 
for  10  minutes,  and  again  wash  thoroughly ;  this  is  to  insure  the  perfect  elimination  of 
the  hypo.  The  least  trace  of  yellowness  after  intensifying  shows  that  the  washing  was 
not  sufficient. 


NEGATIVE-MAKING  —  DRY.  347 

This  fact  seems  to  throw  a  deep  veil  of  difficulty  over  photographic  manipu- 
lation— to  exasperate  even  sometimes,  but  there  is  no  reason  for  being  dis- 
mayed. Choose  a  line  of  practice  and  then  adhere  to  it.  I  never  yet  saw  the 
man  fail  in  our  art  who  was  really  desirous  of  success. 

Flow  sufficient  of  No.  1  over  the  negative  to  cover  it,  and  allow  to  either  partially  or 
entirely  whiten ;  the  longer  it  is  allowed  to  act  the  more  intense  will  be  the  result ;  pour 
off  into  the  sink,  then  flow  over  No.  2,  and  allow  to  act  one  minute ;  wash  off,  and  pour 
over  or  immerse  in  No.  3  until  changed  entirely  to  a  dark  brown  or  black.  No.  3  can  be 
returned  to  its  bottle,  but  Nos.  1  and  2  had  better  be  thrown  away.  Wash  thoroughly 
and  dry. 

Eeduction.  In  cases  of  error  in  development  the  negative  is  too  intense,  the  high 
lights  may  be  safely  reduced  by  the  method  of  Mr.  Howard  Farmer,  viz. :  Ferricyanide 
of  potassium  (red  prussiate  of  potash)  1  oz.,  water  16  oz.,  hyposulphite  of  soda  1  oz., 
water  16  oz. ;  immerse  the  negative  in  sufficient  hypo  solution  to  cover  it,  to  which  have 
been  added  a  few  drops  to  each  ounce  of  the  above  ferricyanide  solution ;  the  speed  of 
reduction  depends  on  the  quantity  of  ferricyanide  present.  When  sufficiently  reduced  wash 
thoroughly.  To  reduce  locally,  apply  the  mixed  solution  to  the  wet  negative  with  a 
camel's  hair  brush  to  the  parts  requiring  reducing. — JOHN  CARBUTT. 

Alkaline  Pyro  Developer  all  in  One  Solution. — This  is  simple,  economical,  and  durable, 
and  the  resulting  negatives  are  extremely  fine  in  color  and  printing  quality.  My  formula 
is  as  follows : 

Stock  solution :  Sulphite  of  soda  (crystals),  3  ounces  troy  weight ;  bromide  of  am- 
monium, $  ounce  troy  weight;  bromide  of  potassium,  1£  ounces  troy  weight;  pyrogallic 
acid,  2  ounces  troy  weight ;  dissolve  thoroughly  in  pure  rain,  distilled,  or  ice  water,  32 
fluidounces;  add  sulphuric  acid  (C.  P.),  120  minims;  finally  strongest  aqua  ammonia, 
3  fluidounces.  Add  water  to  make  up  the  bulk  to  40  ounces. 

Be  careful  to  measure  the  sulphuric  acid  and  the  aqua  ammonia  very  exactly,  and 
keep  the  latter  in  a  cool  place,  well  stoppered,  so  that  it  will  retain  its  full  strength. 

(Instead  of  3  ounces  of  crystals,  2  ounces  of  granular  sulphite  of  soda  may  be  substi- 
tuted to  produce  the  same  effect.) 

The  solution  assumes  a  bright  ruby  color,  and  will  keep  a  long  time  in  a  bottle  with 
tight-fitting  India-rubber  stopper. 

Dilute  sufficient  for  one  day's  use  as  follows : 

For  ordinary  purposes,  1  part  to  11  parts  of  water. 

For  very  short  exposures,  use  1  part  with  3  to  6  parts  of  water. 

For  overexposed  plates,  or  in  all  cases  where  great  intensity  and  contrast  are  desirable, 
1  part  to  20  of  water. 

Always  develop  until  the  shadows  have  sufficient  detail. 

Wash  well  before  fixing  and  prepare  the  fixing  bath  as  follows  :  First  dissolve  a  half 
pound  of  powdered  alum  in  one-third  of  a  gallon  of  water ;  then  dissolve  one  pound  of 
hypo  in  two-thirds  of  a  gallon  of  water.  After  both  are  dissolved,  pour  the  alum  solution 
in  the  hypo.— G.  CRAMER. 

Par  Excellence. — I  will  now  give  you  a  formula  for  a  pyro  developer  that  is  excelled 


348         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

For  the  notes  below  I  have,  from  varied  sources,  selected  what  seem  to 
cover  all  that  has  been  made  known  on  this  vital  topic.  And  yet  I  am  aware 

by  none  ;  is  simple  and  keeps  in  stock  any  length  of  time ;  it  develops  beautifully,  and 

1  consider  it  far  superior  to  the  oxalate : 

Stock,  pyrogallic.  To  1\  ounces  of  common  alcohol  add  \  ounce  of  pyrogallic  acid, 
and  60  grains  of  bromide  of  ammonium  previously  dissolved  in  a  little  water. 

Stock,  bromide  solution.  To  14  ounces  of  soft  water  add  340  grains  of  bromide  of 
ammonium  and  \\  ounces  of  concentrated  ammonia.  Keep  both  of  these  solutions  in 
well-corked  bottles. 

Now,  to  develop,  take  1  drachm  each  of  pyro  solution  and  bromide  solution,  and  add 

2  ounces  of  soft  water.    This  is  sufficient  for  small  plates  up  to  5  x  8,  and  will  develop 
several ;  it  makes  a  very  cheap  developer,  and  after  once  using  you  will  take  no  other. — 

E.  P.  LlBBY. 

In  Three  Solutions. — Well,  let's  see  ;  we  will  take  the  old  method  of  making  the  pyro 
developer  in  three  different  solutions :  No.  1,  pyro ;  No.  2,  bromide ;  No,  3,  ammonia. 
Take  four  drops  of  No.  1,  three  drops  of  No.  2,  and  five  to  ten  drops  of  No.  3. 

I  claim  that  the  most  skilful  worker  cannot  make  his  negatives  of  a  uniform  character 
by  this  method,  and  with  the  careless  operator  it  would  be  simply  impossible;  he  might 
have  his  exposure  right  and  developer  wrong.  Next  plate  he  would  change  his  exposure, 
and  perhaps  his  solution,  too,  and  be  as  far  out  of  the  way  as  ever. 

In  the  above  case  I  will  give  the  palm  to  oxalate.  Now  we  have  a  later  and  simpler 
form  of  the  alkaline  developer :  stock-pyro  in  alcohol ;  No.  1,  pyro  and  water ;  No.  2, 
ammonia,  bromide,  and  water.  To  develop,  take  two  ounces  of  No.  1,  and  five  to  ten 
drops  of  No.  2.  Here,  again,  is  a  chance  for  variation ;  this  drop  business  is  not  right ; 
one  is  apt  to  get  too  many  or  too  few  of  them,  and  with  variable  results.  With  the 
above  method,  as  compared  with  the  first,  the  chances  are  as  two  to  three  in  regard  to 
proportion.  But  by  the  latter  method  plates  can  be  developed  much  more  rapidly  and 
just  as  certainly  as  by  the  oxalate,  and  for  one-fourth  the  cost. — G.  H.  MONROE. 

The  Edwards  Formula. — Now  I  come  to  my  hobby,  the  Edwards  formulae  without  the 
glycerine : 

Stock,  No.  1 :  Pyrogallic  acid,  1  ounce ;  alcohol,  6  ounces.  Stock,  No.  2 :  Bromide  of 
ammonium,  50  grains;  ammonia,  concentrated,  1  ounce;  water,  6  ounces. 

For  the  day's  use  we  have  two  other  bottles  to  hold  sixteen  ounces  each.  Take  one 
ounce  of  No.  1,  fifteen  ounces  of  water;  label  bottle  D.  (developer).  Take  one  ounce  of 
No.  2,  fifteen  ounces  of  water;  label  bottle  A.  (accelerator).  To  develop  (exposure 
proper),  take  equal  parts  of  D.  and  A.  What  can  be  more  simple?  The  development 
is  complete  in  less  than  two  minutes  at  the  most,  and  the  results  are  very  even,  according 
to  the  duration  of  development. 

Now,  if  this  is  not  a  saving  in  time,  bring  on  the  rival  method.  If  a  plate  is  over- 
exposed (5x8  plate  and  tray),  take  two  ounces  of  D.  and  one  ounce  of  A. ;  if  under- 
exposed, one  ounce  of  D.,  two  ounces  of  A. ;  very  simple  and  definite.  Number  of  drops 
of  this  and  drops  of  that  are  oftener  put  in  with  a  squirt  than  carefully  counted.  By 
omitting  the  glycerine,  the  annoying  bubbles  are  done  away  with. — G.  H.  MONROE. 


NEGATIVE-MAKING  —  DRY.  349 

that  in  less  than  a  month  there  may  be  a  hundred  more  offerings  equally  as 
useful.     This  is  as  it  should  be.     In   an  art  so  beautiful  as  ours,  the  more 

To  Keep  Pyro  in  Solution. — I  have  kept  a  three-grain  solution  of  pyrogallic  acid  in 
water  over  a  month  in  perfect  condition,  by  the  use  of  salicylic  acid.  It  does  not  retard 
the  development  in  the  least.  The  proportions  used  are  as  follows :  Pyrogallic  acid,  60 
grains ;  water,  20 .  ounces ;  to  which  add  15  grains  of  salicylic  acid  dissolved  in  2 
drachms  of  alcohol.  This  solution  is  always  ready  for  use  in  equal  quantity  with  the 
solution  of  bromide  and  ammonia,  for  making  the  developer  for  dry  plates.  The  decom- 
position of  pyrogallic  acid  in  aqueous  solution  is  very  similar  to  that  of  other  organic 
substances,  and  is  prevented  in  the  same  way. — D  BACHRACH,  JR. 

Carbonate  of  Soda  Developer. — My  process  consists  simply  in  using  separately  the  pyro- 
gallic acid  bath  and  the  alkaline  bath.  The  mother  solution  of  pyrogallic  acid  prepare 
as  follows :  Sulphite  of  soda,  25  parts ;  distilled  water,  100  parts ;  sulphuric  acid,  3  or  4 
drops ;  pyrogallic  acid,  10  drops. 

I  take  from  10  to  15  parts  (according  to  the  results  that  I  wish  to  obtain),  to  which  I 
add  100  parts  of  water,  and  immerse  my  exposed  plate  in  this  bath.  I  allow  it  to  remain 
at  least  one  minute  or  more — even  from  10  to  15  minutes  would  ca-use  no  injury.  The 
image  commences  to  appear  in  this  bath  on  account  of  the  presence  of  the  sulphite;  but 
it  is  quite  useless,  although  without  danger,  to  await  this  result.  In  the  meanwhile,  I 
prepare  in  another  dish  the  following  alkaline  bath :  Solution  at  25  per  cent,  of  sulphite 
of  soda,  10  parts ;  saturated  solution  of  carbonate  of  soda,  3  parts ;  ordinary  water,  100 
parts. 

The  proportion  of  3  per  cent,  of  the  solution  of  carbonate  of  soda  is  a  minimum  which 
it  would  be  well  to  increase  twofold,  and  even  threefold  if  the  strength  of  the  gelatine 
film  can  bear  it. 

I  now  withdraw  the  plate  from  the  pyrogallic  acid  bath,  and  after  having  allowed  it  to 
drain  two  or  three  seconds,  I  at  once  plunge  it  into  the  alkaline  bath.  The  development 
is  made  with  very  great  rapidity  and  with  a  clearness  explained  by  the  very  small 
quantity  of  pyrogallic  acid  in  the  alkaline  bath.  In  fact,  the  gelatine  film  has  absorbed 
in  a  manner  the  quantity  of  pyrogallic  acid  necessary  for  its  development,  and  nothing 
more ;  from  which  it  results  that  the  alkaline  bath  is  not  sensibly  colored,  neither  is  the 
sensitive  film. 

When  the  exposure  has  been  normal,  the  development  is  ended  in  one  or  two  minutes, 
at  the  most ;  but  it  may  be  prolonged  if  it  is  observed  that  the  intensity  increases  with 
the  duration  of  the  immersion.  It  is  very  rare  that  anything  else  is  necessary  than  to 
wait  in  order  to  obtain  a  perfect  negative.  In  case  the  exposure  has  been  much  too 
short,  it  may  be  necessary  to  add  to  this  last  bath  in  succession  a  little  pyrogallic  acid, 
then  a  little  carbonate  of  soda,  in  order  to  force  the  tardy  details  to  appear ;  but  I  repeat, 
this  should  only  be  done  in  exceptional  cases,  when  very  quick  drops  have  been  used. 
With  exposures  in  the  full  summer  sun  of  from  one-twenty-fifth  to  one-fiftieth  of  a 
second,  I  have  obtained  excellent  negatives,  using  a  little  patience,  without  having 
recourse  to  any  addition  of  pyrogallic  acid  or  of  carbonate. — E.  ANDRE. 

One  more  thing  and  I  am  done.     Commence  the  use  of  dry  pyro  if  a  lot  of  plates  are 


350         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

generous  rivalry  there  is,  the  more  enthusiasm,  and  the  more  enthusiasm  the 
more  growth.  And  development  is  growth  of  the  most  fascinating  description. 
It  affords  as  much  varied  pleasure  too  as  anything  in  art. 

to  be  developed  ;  a  solution  of  two  or  three  grains  per  drachm  can  be  made — or  of  any 
multiple  desired— and  then,  with  little  trouble,  any  amount  needed  can  be  used  quickly, 
cleanly,  and  surely. 

As  it  may  not  have  been  remembered,  or  of  ready  reference,  I  give  the  formula  just  as 
Prof.  Newton  gave  it  : 

No.  1.  Water,  32  ounces;  yellow  prussiate  of  potash,  3  ounces;  carbonate  of  soda,  3 
ounces ;  carbonate  of  potash,  3  ounces.  Mix  and  filter. 

No.  2.  Water,  32  ounces;  sulphite  of  soda,  3  ounces.     Mix. 

In  both  solutions  the  troy  ounce  of  480  grains  is  meant — not  the  avoirdupois  ounce  of 
437 £  grains. 

Normal  Developer:  No.  1.  2  drachms  or  I  ounce.  No.  2.  14  drachms  or  If  ounces. 
Which  makes  up  two  ounces  or  sixteen  drachms,  or  No.  1  one  part ;  No.  2  seven  parts. 
Now,  when  No.  1  and  No.  2  are  mixed,  add  two  grains  of  dry  pyro  for  each  one  ounce  of 
mixed  developer. 

This  is  normal  developer  for  somewhere  near  normal  exposures ;  if  you  have  a  lot  of 
guesswork  plates  to  develop,  make  up  your  pyro  in  No.  2  and  flow  it  over  the  plate,  and 
then  add  the  No.  1,  or  alkali  (?),  in  small  quantities  until  sufficient  detail  and  harmony 
shall  come  out. 

Overexposure  can  be  cured  by  use  of  bromide  of  soda  solution  previously  mentioned, 
or  by  dilution  of  developer,  to  an  extent  that  will  reduce  it  to  a  proportionate  strength 
with  exposure,  but  on.no  account  use  either  bromide  of  ammonium  or  potash  with  this 
developer;  you  will  be  "left"  if  you  do. 

Underexposure,  so  far  as  it  can  be  cured,  can  be  handled  by  increase  of  amount  of 
No.  1  to  several  times  normal. 

This  developer  will  not  bring  out  the  object  if  a  plate  has  been  exposed  y^  the 
proper  time;  nor  will  it  make  so  harmonious  a  negative  in  a  plate  that  has  had  one 
thousand  times  normal  exposure. 

Lastly,  bromide  of  brains  is  one  of  the  most  valuable,  least  used,  of  all  the  essential 
requisites  for  an  "  immature  "  photographer.— THOMAS  PRAY,  JR. 

I  have  been  experimenting  for  two  years  to  obtain  developers  to  take  the  place  of 
ammonia,  that  pernicious  agent  engendering  bronchitis,  deafness,  etc.  Here  is  the 
formula  with  which  I  successfully  work : 

No.  1.  Pyro,  1  part;  sulphurous  acid,  1  part;  distilled  water,  8  parts. 

No.  2.  Saturated  solution  of  carbonate  of  soda,  6  parts;  sulphurous  acid,  1£  parts; 
bichromate  of  potash  solution,  at  5  per  cent.,  J,  £,  or  f  part;  water,  18  parts. 

To  develop  a  half  plate  use  4  c.  c.  No.  1,  and  75  c.  c.  No.  2. 

In  case  of  overexposure,  bromide  may  be  used.  The  development  is  slower  than  with 
ammonia,  and  there  is  a  greater  tendency  to  frill.  Nevertheless  this  last  may  be  obviated 
by  passing  the  plate  through  a  solution  of  sulphate  of  iron  (8  :  80),  to  which  is  added  one 
part  of  tartaric  acid  to  preserve  the  solution.  The  sulphurous  acid  is  only  useful  to 


NEGATIVE-MAKING — DRY. 

That  is,  if  I  dare  apply  the  word  art  to  anything  chemical  or  physical.  If 
I  dare  not,  then  I  shall  claim  that  development  is  more  beautiful  than  art. 

modify  the  color  of  the  developed  image.  I  should  advises  always  to  use  the  iron  bath 
for  fixing,  if  it  is  desired  to  obtain  a  more  rapid  development,  in  omitting  the  sul- 
phurous acid. 

The  plate  should  be  well  washed,  before  and  after  immersion,  in  the  iron  bath.  It 
should  remain  there  from  two  to  five  minutes,  according  to  the  required  time.  The 
longer  it  remains,  the  more  intense  will  be  the  tone.  The  action  of  the  bichromate  is 
curious:  it  accelerates  the  development,  and,  doubtless,  hardens  the  gelatine,  as  when 
it  is  present  there  is  less  tendency  to  frill. — W.  HANSON. 

A  Quick  Method. — For  a  half  plate,  with  an  exposure  of  one  second,  instead  of  six  on 
a  cloudy  day,  use  a  sensitizer  composed  of  150  c.  c.  of  rain  water,  one  drop  of  a  concen- 
trated solution  of  hyposulphite  of  soda,  and  five  drops  of  a  solution  of  bichromate  of 
mercury  at  one  per  cent.  The  plate  is  allowed  to  remain  in  this  bath  for  half  a  minute, 
washed  with  care,  and  developed  with  the  ordinary  oxalate  of  iron.  If  the  print  be  an 
instantaneous  one,  taken  indoors,  the  immersion  should  be  prolonged  for  about  a  minute. 
If  the  print  should  come  too  rapidly,  retard  the  action  of  the  bath  by  a  drop  of  a  con- 
centrated solution  of  citric  acid,  or  by  making  use  of  a  developer  to  which  25  per  cent, 
of  water  has  been  added.  It  is  necessary  to  renew  the  solution  when  it  has  been  used 
for  three  or  four  plates. — HERB,  VERRES. 

Universally  Useful. — In  my  hands  this  will  do  any  reasonable  thing  : 

No.  1.  Pyrogallic  acid,  1  ounce;  water,  4  ounces;  bromide  of  potassium,  600  grains; 
pure  nitric  acid,  20  drops. 

No.  2.  Concentrated  liquid  ammonia,  2  ounces ;  water,  2  ounces. 

Use  four  drops  of  each  to  every  ounce  of  water  required  to  make  up  developer.  If  too 
rapid,  add  two  drops  of  pyro ;  if  too  slow,  add  two  drops  of  ammonia. 

This,  of  course,  is  very  concentrated  and  will  require  careful  use,  as  a  few  drops  either 
way  will  make  a  vast  difference.  Again,  be  sure  you  get  good,  pure  ammonia,  else  you 
will  be  all  at  sea.  Don't  buy  from  a  druggist,  but  from  some  reliable  stockdealer  or 
chemist.  In  all  methods  of  development  this  fact  is  quite  established,  viz.,  that  a  slow 
development  gives  a  finer  grained  negative  than  a  rapid  one,  which  makes  a  coarse 
deposit  and  lacks  detail  in  the  deep  shadows.  In  using  the  sal  soda  developer,  citrate 
of  soda  will  be  found  a  most  powerful  restrainer ;  in  fact,  a  drop  or  two  too  much  is  able 
entirely  to  stop  the  development.  Use  it  carefully,  and  measure  how  much  is  needed 
for  the  particular  brand  of  plates  you  are  using.  Thus  many  an  overexposed  plate  can 
be  saved  by  its  use.  Bromide  of  potassium  is  the  restrainer  accepted  by  the  majority  of 
operators,  it  being  more  active  than  bromide  of  ammonium.  Should  a  slow  plate  be 
used,  then  weaken  the  developer  one-half,  otherwise  very  strong  negatives  will  result 
from  the  use  of  full,  strong  solutions.  Wash  the  pyro  well  off  before  placing  in  the 
hypo,  to  prevent  the  peculiar  pink  stain  often  seen  on  dry  plates.  —  G.  HANMER 
CROUGHTON. 

A  New  Method. — It  has  for  a  long  time  been  my  opinion,  both  from  theory  and  some 
experiments  that  I  made,  that  the  present  method  of  mixing  both  the  pyro  and  alkaline 


352        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Every  plate  I  develop  is  a  new  pleasure  to  me.  I  see  something  iu  it — and 
something  come  out  upon  it  which  I  never  saw  before 

solutions  when  developing,  was  neither  the  best  nor  most  economical  method,  if,  as  I 
think,  we  can  now  mix  up  an  aqueous  solution  of  pyro  tliat  is  stable  and  will  not  change. 
Those  who  understand  the  chemical  action  involved,  are  aware  that  pyro  occupies  almost 
precisely  the  place  of  free  nitrate  of  silver  on  a  collodion  plate,  and  the  sal  soda  or 
ammonia  the  place  of  the  sulphate  of  iron  or  pyro,  whichever  was  used.  Acting  on  this 
theory  I  developed  a  few  plates  by  first  immersing  them  in  a  strong  pyro  solution  for  a 
minute  (which  I  then  drained  off  again  into  the  bottle),  and  then  developing  them  with 
the  sal  soda  solution,  using  the  same  quantity  of  water  as  if  the  solution  had  been  mixed 
in  the  usual  way.  The  result  was  as  good  as  the  best  developed  plates  by  the  other 
methods.  It  will  be  seen  that  several  advantages  are  gained :  First,  the  immersion  in 
strong  pyro  causes  a  uniform  absorption  of  it  all  over  the  plate.  Second,  at  least  two- 
thirds  pyro  is  saved. 

For  plates,  say  up  to  11  x  14  inches  have  a  dipping-bath  (your  old  silver  bath-holder 
will  do,  rubber  as  well  as  glass),  in  which  permanently  keep  the  following  solution  in 
quantity  sufficient  to  cover  the  plate.  An  occasional  filtering  is  all  that  is  necessary  to 
keep  this  in  order  indefinitely. 

Water,  sixteen  ounces ;  sulphite  of  soda,  four  ounces ;  dissolve,  and  add  enough  sul- 
phuric acid  to  turn  litmus  paper  decidedly  red.  Then  add  one  ounce  of  pyrogallic  acid, 
one-quarter  ounce  of  bromide  of  potassium,  and  one  ounce  of  sulphate  of  magnesium. 
When  a  plate  is  to  be  developed,  dip  it  in  this  bath  not  over  a  minute,  then  take  out  and 
drain  it,  and  develop  with  the  alkali. 

Developer,  Stock  Solution.— Crystallized  sal  soda,  £  pound;  water,  1  quart;  sulphite  of 
soda,  i  pound  ;  bromide  of  potassium,  J  ounce. 

Of  this  take  one-half  of  an  ounce  to  two  and  one-half  ounces  of  water,  and  develop  the 
plate  as  usual 

It  will  be  noticed  that  I  put  the  sulphite  of  soda  in  the  second  solution  as  well  as  in 
the  first,  because  so  little  of  the  latter  is  used  that  the  desirable  color  given  by  the  sul- 
phite to  the  plate  would  otherwise  be  absent.  The  sulphate  of  magnesium  is  added  to  the 
first  solution  to  prevent  the  softening  of  the  gelatine  which  is  likely  to  occur  when  the 
solution  is  either  warm  or  tepid. — D.  BACHRACH,  JR. 

This  formula  for  a  potash  developer  is  well  adapted  for  instantaneous  plates. 

No.  I.  Pyro  Solution.— Warm  distilled  or  melted  ice  water,  2  ounces ;  chemically  pure 
sulphite  of  soda  (437  grains  to  ounce),  2  ounces;  when  cool  add:  sulphurous  acid,  2  ounces ; 
and  finally  add:  pyrogallol  (Schering's),  J  ounce  or  218  grains;  which  is  done  by  pouring 
the  sulphite  solution  into  the  pyro  bath,  repeating  the  pouring  until  the  pyro  is  dissolved. 
The  solution,  which  will  now  measure  five  fluidounces,  should  be  filtered,  and  will  contain 
forty-four  grains  of  pyro  to  each  ounce. 

No.  2.  Potash  Solution  is  prepared  by  making  two  separate  solutions  as  follows :  a. 
Water,  4  ounces;  chemically  pure  carbonate  of  potash  (437  grains  to  the  ounce),  3 
ounces,  b.  Warm  water,  3  ounces ;  chemically  pure  sulphite  of  soda  (437  grains  to 
the  ounce),  2  ounces;  a  and  b  are  next  combined  in  one  concentrated  solution,  a  small 


NEGATIVE-MAKING DRY.  353 

And  besides  all  this,  there  is  always  a  mystifying  apprehension  about  it 
which  adds  to  its  charm  and  works  wonders  in  bringing  about  one's  best  results. 

quantity  of  which  when  mixed  with  the  pyro  will  be  sufficient  to  develop  three  or  four 
plates.  The  strength  of  the  solution  will  be  uniform,  and  it  will  measure  between  eight 
and  nine  fluidounces. 

Supposing  a  plate  to  have  been  greatly  overexposed,  or  properly  timed,  or  the  length 
of  the  exposure  is  unknown,  to  develop  a  5  x  8  plate  take  2  ounces  of  water  and  add 
thereto  3  drachms  of  No.  1 ,  and  from  £  to  1  drachm  of  No.  2,  of  the  potash  solution. 
Then  pour  the  solution  upon  the  plate;  after  a  minute's  interval,  should  no  part  of  the 
image  appear,  add  a  second  drachm  of  No.  2,  putting  it  into  the  graduate  first,  and  then 
pouring  the  developer  from  the  tray  into  the  graduate.  The  solution  is  again  flowed 
over  the  plate,  and  if  after  a  minute's  interval  no  image  appears,  repeat  by  adding  a 
drachm  of  No.  2  at  a  time,  until  development  commences.  In  this  way  the  picture  will 
be  brought  out  very  gradually,  the  development  will  be  under  perfect  control,  and  can 
be  prolonged  until  all  details  appear,  without  the  slightest  danger  of  fogging  the  plate. 
The  principle  involved  is  to  add  sufficient  pyro  at  first  to  give  proper  density,  and  then 
add  minute  quantities  of  the  alkali  at  stated  intervals  until  the  right  strength  is  reached 
to  commence  the  development. 

In  place  of  the  No.  1,  or  the  pyro  in  solution,  dry  pyro  may  be  used  with  good  effect, 
6  to  8  grains  being  sufficient  for  2  ounces  of  water. 

If  a  plate  has  had  what  is  termed  a  drop-shutter  exposure,  or,  in  other  words,  an 
instantaneous  exposure,  to  2  ounces  of  water  add  3£  drachms  of  No.  1  and  3  drachms  of 
No.  2,  increasing  it  a  drachm  at  a  time,  in  case  the  shadows  fail  to  come  out,  up  to  5 
drachms. 

The  sky  will  appear  rapidly,  but  the  dark  portions  will  develop  gradually. 

Brilliant,  clear,  bluish-gray  quick-printing  negatives  are  produced  with  this  developer 
on  almost  any  brand  of  plate,  the  necessity  of  using  clearing  solutions  is  avoided,  and 
all  chance  of  stain  to  the  negative  disappears.  The  developing  solution  remains  clear, 
and  from  four  to  eight  plates  may  be  developed  successively  in  it  at  one  time.  Should 
the  negatives  be  too  dense,  the  amount  of  No.  1  may  be  decreased  a  third  to  a  half. 

Among  the  advantages  claimed  for  the  developer  are  simplicity,  certainty  of  uniform 
action,  and  production  of  clear  negatives.  The  solutions  being  in  concentrated  form 
may  be  kept  in  small  bottles,  convenient  for  handling. — F.  C.  BEACH. 

Newton's  Method. — For  a  developer  well  adapted  to  bring  out  fully  the  details  in  a 
plate  which  has  had  a  very  short  exposure,  I  use  the  following : 

No.  1.  Water,  1  ounce;  carbonate  of  soda,  15  grains;  yellow  prussiate  of  potash,  15 
grains ;  sulphite  of  soda,  5  grains. 

No.  2.  Water,  1  ounce ;  chloride  of  ammonium,  7  grains ;  pyro  (dry),  6  grains. 

Nos.  1  and  2  are  mixed,  and  the  whole  poured  over  the  plate.  Development  com- 
mences within  a  minute,  and  is  usually  finished  at  the  end  of  three  or  four  minutes. 
The  proportions  named  above  are  correct  for  an  ordinary  drop-shutter  exposure,  but  they 
are  not  arbitrary ;  they  may  be  varied  to  suit  different  cases,  as,  for  example,  should  the 
plate  have  been  greatly  underexposed,  equal  parts  of  Nos.  1  and  2  (with  the  pyro  left 

23 


354        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  student  must  not  be  alarmed  at  this  variety,  for  even  in  nature  it  is  rare 
to  find  either  fruit  or  flower  developed  and  brought  to  perfection  twice  alike. 

out  of  the  latter)  may  be  added,  a  little  at  a  time,  to  from  three  to  four  times  the  strength 
stated,  until  all  the  details  in  the  shadows  are  brought  out,  without  danger  of  producing 
green  fog,  which  frequently  appears  from  the  excessive  amount  of  ammonia  sometimes 
used  in  the  ordinary  ammonia  and  pyro  developer.  In  case  of  overexposure,  half  a 
grain  to  the  ounce  of  developer  of  bromide  of  sodium  is  added,  and  the  solution  diluted 
with  water. 

Nos.  1  and  2  solutions  may  be  kept  in  a  more  concentrated  form,  and  diluted  for  use. 
The  following  are  the  right  proportions  for  10  per  cent,  solutions  : 

No.  1.  Water,  9J  ounces;  carbonate  of  soda,  480  grains;  yellow  prussiate  of  potash, 
480  grains;  sulphite  of  soda,  160  grains. 

No.  2.  Water,  9  ounces ;  chloride  of  ammonium,  510  grains ;  solution  of  one  drop  of 
sulphuric  acid  in  one  ounce  of  water,  1  drop;  pyro  (one  commercial  ounce)  437  grains. 

If  No.  2  does  not  change  from  a  purple  color  to  a  clear  yellow  color  within  an  hour 
after  mixing,  one  or  two  drops  more  of  the  sulphuric  acid  solution  may  be  added. 

To  prepare  a  developer  of  the  proper  strength  with  the  above  solutions  for  the  de- 
velopment of  a  5x8  plate  which  has  had  a  drop-shutter  exposure,  take :  Water,  5£ 
drachms;  No.  1  solution,  2f  drachms.  Also:  Water,  7  drachms;  No.  2  solution,  1 
drachm.  Mix  the  two,  and  develop  in  the  usual  way. — H.  J.  NEWTON. 

Mr.  Bachrach's  Plan. — Without  going  into  the  reasons  and  the  theory  involved,  I  will 
simply  give  the  formula  as  I  now  use  it.  In  our  establishment  we  only  use  it  for  plates 
of  less  than  11  x  14  inches  measurement,  preferring  the  usual  formulae  for  larger  plates. 
The  solution  No.  1,  of  pyrogallic  acid,  etc.,  is  to  be  used  in  a  regular  dipping  bath,  into 
which  the  plates  are  to  be  dipped  before  development  in  the  alkaline  solution.  No.  2  is 
the  developing  solution  into  which  the  plates  are  removed  after  dipping  in  the  bath. 

No.  1.  Pyrogallic  acid,  2  ounces;  water,  16  ounces;  sulphate  (not  sulphite)  of  soda, 
£  ounce ;  bromide  of  potassium,  J  ounce. 

Dissolve,  and  add  to  this  solution  4  ounces  of  sulphite  of  soda,  dissolved  in  15  ounces 
of  hot  water,  made  slightly  acid  after  dissolving  with  sulphuric  acid  to  C.  P.  Then  add 
30  grains  of  salicylic  acid  dissolved  in  1  ounce  of  glycerine  and  £  ounce  of  alcohol.  This 
solution  keeps  indefinitely,  and  will  also  answer  as  well  for  developing  the  usual  way. 

No.  2.  Sal  soda,  1  pound;  sulphite  of  soda,  1£  pounds;  water,  1  gallon. 

When  ready  for  developing,  make  up  the  developer  by  using  1  part  of  No.  2  solution 
to  two  parts  of  water ;  make  plenty  of  it,  as  it  works  better  in  large  quantities  and  is 
cheap.  Dip  the  plate  from  ten  seconds  to  half  a  minute  in  No.  1  solution,  and  then 
remove  to  a  dish  containing  the  developer  prepared  as  above.  They  will  develop 
regularly,  and  you  may  leave  the  plates  in  until  fully  developed.  If  the  time  of  dipping 
in  the  pyro  has  been  carefully  noted,  by  using  one  brand  of  plates,  accuracy  can  soon  be 
acquired.  No  fear  need  be  had  of  too  much  density,  as  the  plate  has  absorbed  only  a 
certain  quantity  of  pyro,  and  consequently  the  high  lights  cannot,  as  in  the  ordinary 
method,  be  "  piled  up "  by  continued  development.  The  latter  only  occurs  with  this 
method  when  dipped  too  long  in  the  pyro,  and  when  this  is  noted  by  the  way  the  plate 


NEGATIVE-MAKING  —  DRY.  355 

A  few  words  on  the  rationale  of  development  should  come  in  right  here  for 
the  help  of  the  novice,  before  we  proceed  any  further. 

develops,  it  is  only  necessary  to  add  water  to  the  developing  solution,  and  it  can  be 
remedied.  When  the  plate  has  been  overexposed,  or  is  suspected  of  having  been,  dip  it 
a  longer  time  in  the  bath  ;  if  underexposed,  a  shorter  time.  Want  of  contrast  can  be 
cured,  if  taken  in  time,  by  adding  pyro  solution  to  the  developer ;  but  this  is  only  liable 
to  occur  with  overexposure  or  too  short  immersion  in  the  pyro.  Different  brands  of 
plates  require  variations  in  time  of  dipping. 

The  advantages  of  this  method  of  developing  are  greater  uniformity  of  results,  a  closer 
resemblance  to  wet-plate  effects,  and  a  great  saving  of  pyro.  In  summer  it  is  necessary 
to  keep  No.  1  solution  cool. — D.  BACHRACH,  JR. 

My  Developer. — I  have  tried  nearly  every  formula  published,  and  have  found  that  the 
Cooper  developer  is  the  simplest  and  the  best  that  I  have  used.  It  is  prepared  as 
follows . 

No.  1.  Sulphite  of  soda,  J  pound;  pure  water,  2  quarts;  pyrogallic  acid,  2  ounces. 

No.  2.  Carbonate  of  soda,  pure,  crystals,  J  pound ;  water,  2  quarts. 

To  develop,  take  No.  1,  2  ounces ;  No.  2,  2  ounces ;  water,  2  ounces. 

The  developer  can  be  used  until  it  turns  a  dark  color. 

For  fixing,  I  use  the  following :  Put  three  pounds  of  hypo  soda  in  a  gallon  bottle, 
nearly  fill  with  water ;  after  the  hypo  is  dissolved  add  four  ounces  of  chrome  alum 
solution.  After  it  settles  it  can  be  used. 

The  chrome  alum  solution  is  prepared  as  follows:  Chrome  alum,  1  pound;  water, 
5  pints. 

The  chrome  alum  will  impart  a  greenish  color  to  the  fixing  bath.  When  this  color 
disappears,  the  bath  should  be  renewed. 

With  the  above  developer  and  fixing  bath  I  have  no  trouble  with  fog  or  frilling. — 
WILLIAM  McCoMB. 

Worth  notice,  also,  is  the  communication  of  Stolze,  according  to  which  the  bromide 
of  silver  gelatine  can  be  mixed  with  pyrogallic  acid  and  sulphite  of  soda.  When  dried 
and  exposed,  these  plates  will  develop  in  a  simple  soda  solution.  The  possibility  is 
therefore  determined  that  the  manufacturer  of  the  emulsion  can  add  at  once  the  neces- 
sary quantity  of  pyrogallic  acid;  this  being  a  great  convenience  and  a  saving  of  much 
time  for  travelling  photographers.  Meydenbauer  asserts  that  the  sensitiveness  of  the 
plates  is  increased  by  this  addition.  About  the  durability  of  such  emulsions  no  obser- 
vations have  been  made,  except  one  of  six  weeks. 

I  introduced  with  success  in  April,  1885,  the  sulphate  of  ammonia  in  the  pyro  devel- 
oper; and  on  May  5,  1885,  he  communicated  to  the  Vienna  Photographic  Society  his 
discovery  of  the  property  of  hydrazine  (particularly  the  phenilhydrazine  as  sent  to  him 
by  Dr.  Walter,  of  Basle)  acting  in  alkaline  solutions  as  a  developer  for  transparent  pic- 
tures upon  bromide  and  chloride  of  silver. — DR.  J.  M.  EDER. 

Developer  proposed  by  M.  de  la  Motte:  A.  Water,  100  c.  c.  (3  fl.  ozs.  3  fl.  drs.) ;  car- 
bonate of  ammonium,  25  grs.  (386  grains);  bromide  of  potassium,  1.2  grs.  (18  grains). 
A.  Water,  100  c.  c.  (3  fl.  ozs.  3  fl.  drs.) ;  carbonate  of  ammonium,  25  grs.  (386  grains).  Or, 


356         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

After  the  sensitive  plate  has  been  exposed  in  the  camera,  it  holds  what  is 
termed  a  latent  image.     Exposed  to  the  light  in  that  condition  the  obscuration 

B.  Water,  100  c.  c.  (3  fl.  ozs.  3  fl.  drs.) ;  carbonate  of  soda,  25  grs.  (386  grains) ;  bromide 
of  ammonium,  1  gr.  (15  grains).  B.  Water,  100  c.  c.  (3  fl.  ozs.  3  fl.  drs.) ;  carbonate  of 
soda,  25  grs.  (386  grains) 

The  plate  having  been  washed  in  water  for  five  or  six  minutes,  is  plunged  into  a  dish 
containing  (for  a  plate  18  x  24  centimetres)  (7|  x  9£  inches)  125  c.  c.  (3  fluid  ounces  10 
drachms)  of  a  solution  of  pyrogallic  acid  at  1  per  cent.,  well  mixed  with  from  12  to  15  c.  c. 
(3  to  4  fluid-drachms)  of  good  beer,  and  is  allowed  to  remain  in  this  liquid  for  about  one 
minute. 

The  plate  is  then  removed;  4  or  5  c.c.  (1  to  1J-  drachms)  of  the  solution  A  or  the  solu- 
tion B  are  added  to  the  bath,  and  the  plate  is  again  plunged  for  30  or  40  seconds ;  the 
image  will  not  yet  show  itself.  3  c.  c.  (49  minims)  of  A,  and  2  c.  c.  (32  minims)  of  A,  or 
3  c.  c.  (49  minims)  of  B,  and  2  c.  c.  (32  minims)  of  B  are  added,  and  the  plate  is  again 
immersed  for  about  half  a  minute ;  the  image  will  now  appear.  The  development  may 
be  continued  if  it  is  necessary,  by  adding  more  or  less  of  A  and  A,  or  of  B  and  B,  as  may 
be  required. 

If  a  solution  of  sodium  is  used  for  the  development  of  gelatino-bromide  negatives, 
corresponding  with  colors  that  are  strongly  non-actinic,  too  great  a  degree  of  intensity 
may  be  obtained,  and  it  is  better  to  remedy  it  by  underexposure. 

After  an  ammoniacal  development,  it  is  possible  to  obtain  all  degrees  of  intensity,  and 
if  this  were  insufficient,  the  image  must  be  strengthened  by  a  mixture  of  pyrogallic  and 
acetic  acid,  containing  about  ten  per  cent,  of  beer. — LEON  VIDAL. 

Dr.  Monckhoven's  plan :  I  herewith  give  Dr.  Monckhoven's  developer  as  I  am  now 
using  it :  Place  upon  the  stove  and  boil  a  teakettle  full  of  water. 

No.  1.  Boiling  water,  about  24  ounces;  sulphate  of  iron,  6  ounces;  oxalic  acid,  3 
ounces.  No.  2.  Boiling  water,  24  ounces;  neutral  oxalate  of  potash,  8  ounces. 

To  make  the  developer — 1st.  In  a  small  granite-ware  or  porcelain-lined  kettle  put  the 
six  ounces  of  iron,  and  pour  about  the  above  amount  of  boiling  water  upon  it,  stirring  it 
with  a  rod;  in  about  one  or  two  minutes  it  will  be  dissolved.  Then  add  the  crystals  of 
oxalic  acid,  and  stir  for  a  moment,  when  the  iron  will  be  converted  into  a  yellow  precipi- 
tate of  oxalate  of  iron,  which  in  two  or  three  minutes  will  settle  to  the  bottom  of  the 
dish,  after  which  the  water  should  be  carefully  decanted  off,  leaving  the  iron  in  the  bot- 
tom of  dish ;  about  the  same  amount  of  fresh  hot  water  should  be  added  and  well  stirred, 
and  again  allowed  to  settle  and  be  decanted.  This  operation  should  be  performed  four 
or  five  times,  or  until  the  acid  used  is  completely  washed  out  of  the  iron. 

2d.  In  the  meantime  the  oxalate  of  potash  is  to  be  dissolved  in  about  twenty-four 
ounces  of  boiling  water,  and  after  the  last  washing  has  been  decanted  from  the  iron,  the 
potash  solution  is  turned  upon  it,  and  it  is  placed  over  the  stove  and  stirred  for  about 
five  minutes,  when  the  iron  will  all  be  taken  up  by  the  potash.  When  cooled  to  85°  F.; 
it  is  ready  to  use.  This  makes  a  saturated  solution  of  ferrous  oxalate,  and  if  used  of 
this  strength  will  develop  a  fully  exposed  plate  in  about  ten  seconds.  In  practice  this 
is  too  energetic  to  permit  a  proper  examination  of  the  work;  therefore  I  divide  the  solu- 


NEGATIVE-MAKING  —  DRY.  357 

of  the  film  would  ensue  and  prevent  all  chance  of  the  latent  image  ever  be- 
coming apparent,  by  whatever  means  applied.  But  if  it  is  protected  from  the 

tion  into  two  parts,  one  of  which  I  weaken  with  water  until  it  will  consume  one  to  three 
minutes  in  the  development.  The  advantages  of  this  developer  are  that,  by  the  simple 
addition  of  water,  you  can  adapt  it  equally  to  the  most  delicate  draperies  and  lightings, 
or  hardness  and  strength,  that  are  attainable  by  the  old  wet  process.  An  underexposed 
negative  can  nearly  always  be  brought  up  to  good  printing  qualities  with  the  strongest 
developer,  and  it  is  possible  to  make  exposures  of  an  eighth  of  a  second  or  less  in  the 
studio,  with  good  results,  by  its  use. — J.  H.  SCOTFORD. 

Ferrous  Oxalate  Developer  in  Concentrated  Solution. — By  following  the  indications  given 
by  Dr.  Eder,  I  have  made  the  following  concentrated  solution :  Boiling  water,  500 
grammes;  neutral  oxalate  of  potash,  300  grammes. 

This  solution  made,  to  the  same  liquid  at  95°  C.  (203°  F.)  we  have  added  sulphate 
of  iron,  100  grammes;  when  all  was  dissolved,  we  filtered  this  liquid  into  well-stoppered 
bottles.  In  use,  this  is  what  we  observed:  An  exposed  plate  plunged  into  this  developer 
gives  but  faint  traces  of  the  image  to  be  developed,  but  the  intensity  increases  when 
water  is  added  to  the  concentrated  liquid.  By  adding  an  equal  volume  and  even  double 
the  volume  of  the  solution,  we  have  obtained  very  complete  development.  When  devel- 
oping plates  that  have  had  a  normal  exposure,  we  can  at  once  use  three  times  the  volume 
of  the  concentrated  solution.  If,  on  the  contrary,  overexposure  is  feared,  the  water 
should  be  added  gradually.  A  prolonged  stay  in  concentrated  solution  retards  the  com- 
ing of  the  image,  instead  of  rendering  it  more  intense.  A  plate  immersed  in  water, 
before  being  treated  with  the  concentrated  developer,  does  not  develop  any  better  in  it, 
unless  at  least  the  proportion  of  the  additional  water  be  increased  twofold.  To  resume, 
this  concentrated  solution  offers  the  advantage  of  reducing  to  a  minimum  a  solution  of 
ferrous  oxalate  ready  for  use;  by  the  addition  of  more  or  less  ordinary  water,  it  is  pos- 
sible better  to  conduct  the  development  of  overexposed  negatives. — LEON  VIDAL. 

Try  my  developer:  A.  Hot  soft  water,  7  ounces;  sulphite  of  soda,  2  ounces;  when 
cold,  add  pyrogallic  acid,  1  ounce;  salicylic  acid,  6  grains,  dissolved  in  half  gallon  alco- 
hol. For  use,  add  7£  ounces  of  water  to  £  ounce  of  solution  A.  B.  Hot  water,  57  ounces; 
sulphite  of  soda,  2  ounces;  carbonate  of  potassium,  2  ounces. 

To  develop  a  5  x  7  plate,  use  1  ounce  of  A  with  1  ounce  of  B.  To  secure  more  inten- 
sity, use  more  of  A,  or  if  too  much  intensity,  I  use  less  of  A  and  more  of  B.  I  do  not 
know  as  this  is  new,  but  I  have  not  seen  it  put  up  in  this  form. — CHARLES  KNOWLTON. 

A  New  Sulphite  of  Ammonia  Developer. — I  have  fully  recognized  the  value  of  a  potash 
developer  for  rapid  plates  and  short  exposures;  but,  notwithstanding  this,  I  recommend 
a  new  developer,  containing  ammonia  and  ainmoniacal  sulphite,  which  is  excellent  for 
almost  all  commercial  plates:  A.  Dissolve  10  parts  of  pyrogallic  acid  and  from  25  to  30 
parts  of  ammoniacal  sulphite  in  100  parts  of  water.  B.  Dissolve  5  parts  of  ammoniacal 
bromide  in  150  parts  of  water,  and  add  50  parts  of  liquor  ammonia. 

To  make  the  developer,  take  100  c.  c.  of  water,  4  c.  c.  of  the  pyrogallic  solution  A,  and 
4  c.  c.  of  the  alkaline  solution  B. 

The  development  is  very  quickly  made,  and  if  slower  action  is  required,  add  50  c.  c. 


358         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

light,  and  developing  solutions  applied  immediately  a  real  image  begins  to 
form.  A  building-up  process  commences.  The  particles  of  reduced  silver 

of  water,  which  gives  softer  images.  On  the  other  hand,  if  we  wish  to  obtain  stronger 
images,  add  a  few  drops  of  a  ten  per  cent,  solution  of  ammoniacal  bromide. 

The  ammoniacal  sulphite  developer  gives  well-modelled  and  brilliant  negatives,  in 
which  the  high  lights  are  well  rendered  and  the  deep  blacks  well  defined;  the  negatives 
have  a  very  agreeable  dark  brown  tone.  The  ammoniacal  sulphite  renders  the  pyrogallic 
solution  more  permanent  than  does  the  sodic  sulphite,  and  with  this  developer  there  is 
not  much  danger  of  fogging. — DR.  J.  M.  EDER. 

Formula  for  Development  with  Hydrokinone. — I  have  been  trying  hydrokinone  (i  gr. 
hydrokinone  to  the  ounce)  for  ordinary  Wratten  &  Wainwright  plates.  Exposed  fifteen 
seconds  to  the  north  sky  (clear),  with  stop  (f-42) ;  ordinary  negatives;  working  positives 
on  the  3]  plate.  Manner  and  results  as  follows:  Soaked  one  minute  in  water,  and  one 
minute  in  f  gr.  hydrokinone  to  ounce,  then  added  £  dr.  ammonia  to  ounce.  In  6  minutes 
faint  image  appears,  in  10  minutes  (from  last  note)  I  recognize  picture,  in  14  minutes 
detail  out  very  faint,  and  in  21  minutes  intense  enough  for  transparency.  Fixed  and 
yello wish-red  green  fog,  not  removable  by  Edwards'  modification  of  Cowell's  clearing 
solution  (1  oz.  alum,  1  oz.  citric  acid,  and  3  ozs.  iron  to  20  ozs.  water),  nor  by  bleaching 
with  ferric  oxalate,  or  re-development  by  ferrous  oxalate  developer.  The  same  exposure 
with  same  plates  develops  beautifully  with  J  dr.  ammonia,  i  gr.  bromide  of  potassium, 
and  1  gr.  pyro  to  oz.,  with  perfectly  clear  shadows.  Using  the  sulpho  pyrogallol  of  the 
Platinotype  Company,  it  took  five  minutes  before  they  showed  the  faintest  image ;  in 
fact,  development  very  slow. — DR.  H.  L.  VERCOE. 

The  solution  of  hydroquinohe  in  alkaline  sulphites,  on  the  contrary,  remains  perfectly 
white  for  a  certain  length  of  time,  and  it  is  with  it  that  I  propose  to  operate.  In  100 
parts  of  a  solution  of  «oda  at  10  for  100,  I  dissolve  1  part  of  hydroquinone;  I  steep  my 
impressioned  plate  two  or  three  minutes  in  the  bath,  and,  without  draining  it,  I  plunge 
it  into  an  ordinary  ammoniacal  pyrogallic  developer  without  sulphite.  The  image 
appears  with  all  its  details,  and  the  bath  does  not  acquire  a  dark  color.  If  the  negative 
is  a  little  gray,  I  add  a  few  drops  of  an  aqueous  solution  of  hydroquinone  at  1  for  100 ; 
that  I  make  at  the  time,  and  in  very  small  quantity.  In  this  manner  I  obtain  negatives 
that  are  perfectly  clear,  of  a  beautiful  red-brown  color,  eminently  favorable  for  printing. 
The  sulphite  bath  may  be  used  until  exhausted.  The  pyrogallic  bath  may  serve  several 
times,  and,  moreover,  the  addition  of  a  few  drops  of  the  hydroquinone  solution  of  1  for 
100  increases  but  very  little  the  cost.  I  have  not  tried  hydroquinone  with  the  alkaline 
carbonate  developers,  but  I  believe  that  it  would  render  great  service  in  intensifying  the 
negatives,  after  the  appearance  of  the  details  in  the  pyrogallic  bath,  especially  in  the 
process  recently  recommended  by  M.  Balagny. — M.  E.  JOLY. 

Any  one  accustomed  to  the  various  processes  to  which  a  photograph  may  be  subjected 
is  convinced  that  a  slow  or  gradual  development  has  many  advantages  over  a  rapid 
development. 

Although  a  strong  developer  will  compensate  more  for  a  shorter  exposure  than  a 


NEGATIVE-MAKING — DRY.  359 

run,  spring,  leap,  climb,  pile  up,  fall  into  their  places  just  as  the  sand  of  the 
simoom  and  the  snow  of  the  mountain  do  and  form  the  elevations  and  depres- 

weak  developer,  yet  even  in  the  wet  process,  with  the  exception  of  some  peculiar  cases, 
a  weak  developer  is  to  be  preferred. 

Above  all,  a  weak  developer  works  more  clearly  and  uniformly  than  a  stronger  one, 
and  requires  less  skill  in  manipulation.  This  is  especially  apparent  in  the  production 
of  large  photographic  landscapes,  without  which  it  is  almost  impossible  to  represent  an 
atmospheric  effect  with  success. 

The  image  produced  by  a  weak  developer  is  more  harmonious  in  its  general  character ; 
and  in  the  photographing  of  interiors  it  gives  that  uniformity  in  gradation  of  tones 
which  is  so  desirable. 

The  dark  portions,  which  are  a  constant  factor  in  interiors,  have  more  chance  to 
develop  and  bring  out  the  detail.  Moreover,  there  is  no  danger  of  making  the  high 
lights  too  intense,  which  would  occur  if  a  strong  developer  was  employed. 

Cases  not  infrequently  occur  in  which  a  peculiar  constitution  of  the  developer  is 
demanded,  as,  for  instance,  in  the  reproduction  of  engravings  or  line  drawings,  more 
acid  must  be  added  to  it  than  is  used  in  the  development  of  portraits  or  in  landscape 
photography. 

A  weaker  developer,  in  consequence  of  the  slowness  of  the  deposition  of  the  silver, 
gives  a  far  more  delicate  and  pleasing  image  than  can  ever  be  hoped  for  with  a  strong 
developer. 

Transparent  positives  are  more  pleasing  in  every  respect  when  slowly  developed. 

The  same  remarks  seem  applicable  to  the  modern  dry-plate  development. 

It  is  said  that  the  oxalate  development  gives  negatives  which  have  greater  resemblance 
to  those  produced  by  the  wet-plate  process,  but  we  can  assert  with  positiveness  that  the 
artistic  effect  produced  by  pyro  development  far  transcends  the  effect  to  be  obtained  by 
the  use  of  oxalate. — DR.  H.  STURENBERG. 

A  Plea  for  Over-timing. — One  thing  experience  has  taught  me — that  is,  whenever  it  is 
possible  to  overtime  a  picture  do  it,  and  when  you  come  to  develop  you  won't  regret  it. 

Make  the  following  solutions : 

No.  1.  Pyro,  1  ounce;  sulphite  of  soda,  2  ounces;  bromide  of  potassium,  40  grains; 
citric  acid,  40  grains;  water,  12  ounces. 

No.  2.  Carbonate  of  potassa,  3  ounces;  sulphate  of  soda,  2  ounces;  water,  12  ounces. 

Take  one  drachm  of  No.  1  to  one  ounce  of  water,  and  add  ten  drops  of  (ten  grammes 
to  ounce)  solution  of  bromide  of  potassium.  Let  the  plate  be  in  it  for  a  minute,  then 
pour  off  its  solution,  and  cautiously  add  No.  2,  beginning  with  one-quarter  of  a  drachm 
to  every  ounce  of  the  solution ;  wait  two  minutes  before  you  get  frightened  at  the  non- 
appearance  of  the  image ;  be  assured  if  you  have  overtimed  there  is  plenty  of  what  the 
philosophers  call  potential  energy  to  work  out  its  own  salvation.  After  the  two  minutes 
are  up,  you  may  add  another  one-quarter  of  a  drachm  of  No.  2,  and  keep  right  on  de- 
veloping not  too  rapidly.  If,  in  adding  the  first  one-quarter,  the  image  comes  up  in 
less  than  a  half  minute,  lift  the  plate  immediately  from  the  solution,  and  lay  it  in  a 
bath  of  bromide  of  potassium,  one  drachm  to  the  ounce  (ten  grain  solution),  and  keep  it 


360        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

sions  we  see.  A  sectional  view  of  a  developed  image  is  a  miniature  in  drawing 
of  what  a  sectional  view  of  the  earth  snow  covered,  sand  scattered  would  be. 

there  a  couple  of  minutes ;  then,  without  washing,  put  it  back  in  the  solution,  and  it 
will  work  out  slowly  and  beautifully. 

Always  begin  with  the  weak  developer;  keep  a  stock  on  hand  for  the  purpose. 
Another  thing  which  I  have  learned — don't  be  stingy  or  saving  with  weak  developer  ; 
you  may  have  to  pay  for  it  in  the  loss  of  a  negative.  Overtimed  negatives  are  beautiful 
and  soft  if  managed  in  this  way.  I  have  used  the  most  rapid  plates,  and  given  them  ten 
times  too  much  exposure,  and  yet  by  this  method  obtained  the  best  finished  negatives  I 
have ;  but,  sometimes,  you  cannot  overtime.  Well,  then,  this  is  the  way  I  manage :  I 
take  the  plate  from  the  holder,  lay^it  in  plain  water  for  two  minutes,  covering  it  up,  of 
course ;  I  then  wash  it  by  pouring  water  over  it,  place  it  in  solution  composed  of  one 
ounce  of  water,  one  drachm  of  No.  1  or  No.  2  and  go  on  with  the  development.  In  nine 
cases  out  of  ten  it  will  come  up  like  a  full-timed  negative.  It  is  strange,  but  it  is  a  fact, 
that  the  washing  after  removal  from  the  plain  water  facilitates  the  development.  If  the 
plate  should  still  lack  details  in  the  shadows,  I  lift  it  out  and  transfer  it  to  a  dish  con- 
taining one  ounce  of  water  to  one  drachm  of  No.  2,  and  let  it  lie  a  half  minute,  then 
return  it  to  the  mixed  developer.  I  prefer  this  to  adding  the  accelerator  directly  to  the 
developer. 

Be  sure  to  let  the  plate  lie  in  the  developer  till  it  has  density  enough,  but  be  careful 
not  to  get  it  too  dense. 

It  is  a  good  plan  to  develop  one  plate,  and  fix  it,  and  see  how  far  you  have  gone  in 
intensification ;  then,  with  that  experience,  go  back  and  develop  the  rest. 

My  parting  advice  is,  use  the  quickest  plates  for  all  subjects,  and  overtime  them,  and 
you  will  be  happy. — EUGENE  ALBERT. 

A  Method  of  Treating  Plates  whose  Time  of  Exposure  is  Unknown. — On  developing  my 
American  plates  I  worked  upon  the  supposition  that  I  did  not  accurately  know  the  times 
of  exposure.  I  could  not  definitely  say  whether  a  certain  plate  had  been  over-  or  under- 
exposed. 

I  therefore  proceeded  as  follows :  The  plates  were  first  of  all  laid  in  a  solution  of  150 
c.  cm.  of  neutral  oxalate  of  potassa  (1  to  3),  and  only  5  c.  cm.  of  iron  (1  to  3),  and  the 
appearance  of  the  image  watched  for. 

If  the  outlines  of  the  image  began  to  appear  in  about  a  minute  and  a  half  the  exposure 
was  considered  right. 

They  were  then  left  in  the  bath,  while  a  second  bath  was  prepared :  150  of  oxalate  of 
potassa,  10  of  iron.  Number  one  was  placed  in  this,  whilst  a  second  plate  was  put  in 
the  first  bath. 

In  bath  No.  2  the  second  plate  was  allowed  to  develop  further. 

When  it  was  found  that  no  further  detail  could  be  got  from  the  second  bath  it  was  put 
in  a  third :  150  oxalate  of  potassa,  20  of  iron.  This  VMS  sufficient  generally  to  develop 
the  plate  fully. 

Now  as  regards  the  treatment  of  underexposed  plates : 

Two,  or  even  three,  minutes  was  often  not  enough  to  bring  out  even  the  high  lights  in 


NEGATIVE-MAKING  —  DRY.  361 

I  am  sure  you  understand.  No  small  number  of  the  particles  of  silver  go 
adrift  and  find  no  place  in  building  up  the  image.  Some  of  these  are  driven 

No.  1.  They  were  placed  respectively  in  Nos.  2,  3,  and  4,  and  allowed  to  finish  in  tne 
latter. 

If  the  plates  came  up  very  rapidly  in  No.  1,  they  were  immediately  transferred  to  a 
bath  of  the  same  strength,  to  which  from  five  to  den  drops  of  bromide  of  potassium  were 
added.  The  development  was  in  this  way  retarded,  and  a  plate  of  sufficient  intensity 
produced. 

The  baths  were  always  strengthened  after  three  or  four  plates  had  been  developed 
therein,  or  a  new  bath  made. 

In  this  manner  the  plates  were  developed  slowly  and  regularly ;  sometimes  a  half  hour 
elapsed  before  a  plate  left  the  final  developer.  They  were  usually  intense  enough,  and 
rarely  needed  any  strengthening.  Some,  however,  did  need  a  little  doctoring.  I 
remember  some  of  the  plates  which  I  had  taken  in  the  high  plains  of  Arizona  and  New 
Mexico.  I  had  given  them  an  average  exposure  of  seven  seconds  with  smallest  stop,  an 
exposure  which  had  been  shown  to  be  correct  for  some  negatives  taken  upon  the 
Northern  Pacific  Railroad,  but  at  this  elevation  the  exposure  was  too  long,  and  the 
plates,  as  a  matter  of  course,  were  overexposed. 

It  is,  therefore,  true,  as  Bunsen  has  shown,  that  the  actinic  force  is  greater  in  high 
altitudes  than  upon  the  sea  level,  but  I  had  no  idea  the  difference  is  so  great. 

Over-developed  plates  I  subjected  to  this  process  of  reduction  with  iodine  already 
mentioned.  I  cannot,  however,  recommend  the  cyanide  of  potassium.  The  reduction  is 
more  under  control  with  the  former.  The  plates  are  laid  in  a  solution  of  iodine  and 
iodide  of  potassium,  recommended  above  for  the  removal  of  green  fog ;  they  axe  then 
put  in  the  fixing  hypo,  by  which  the  iodide  of  silver  formed  is  dissolved.  If  they  are 
not  clear  enough,  repeat  the  process. 

Finally,  you  will  perceive  that  the  negatives  give  perfectly  clear  shadows.  If  they 
look  thin,  strengthen  them  with  bichloride  of  mercury  and  ammonia. 

The  atelier  photographer  may  laugh  over  the  amount  of  pains  to  save  a  badly  exposed 
plate,  but  he  forgets  that  he  does  not  have  to  travel  miles  and  miles  to  secure  his  object. 
The  amount  of  labor  expended  upon  anything  increases  its  intrinsic  value,  if  not  its 
exchangeability.  The  portraitist,  when  he  has  made  a  bad  negative,  need  only  turn 
smilingly  back  to  his  subject  and  say,  "You  have  slightly  moved ;  I  think  I  can  improve 
it  by  another  exposure." 

And  we  try,  conscientiously,  all  in  our  power,  to  get  what  we  can  from  our  plates. 

A  skilful  amateur,  present  during  my  development,  was  astonished  that  I  should 
devote  so  much  time.  But  patience  is  a  virtue  of  our  race. — DR.  H.  W.  VOGEL. 

If  photographers  in  general  would  use  a  little  more  judgment  in  the  development  of 
dry  plates,  there  would  be  fewer  complaints,  fewer  failures — more  profit  and  greater 
satisfaction  to  all,  from  the  plate-maker  to  the  customer  who  gets  the  photographs.  It 
will  never  do  to  condemn  a  plate  because  it  does  not  happen  to  give  satisfactory  results 
by  the  same  development  and  treatment  that  another  one  gives  all  that  can  be  desired 
by.  A  plate  which  is  inclined  to  give  hardness  must  have  a  very  different  treatment 


362         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

away  by  the  wash-water,  and  the  most  persistent  ones  are  "  cleared "  off  by 
the  fixing  process.  The  entire  operation  is  fascinating. 

from  the  one  that  tends  to  weakness  and  flatness  of  image.  The  former  should  be  de- 
veloped with  a  very  weak  solution  of  pyro — not  more  than  from  one  to  two  grains  to  the 
ounce ;  this  will  necessarily  require  a  longer  exposure  than  one  which  is  to  be  treated  by 
the  opposite.  A  plate  giving  a  thin,  flat  image  with  the  developer  at  this  strength  of 
pyro  will,  if  nothing  else  be  the  matter,  give  all  that  can  possibly  be  desired  by  using 
from  four  to  five  grains  to  the  ounce  of  solution  of  ammonia,  potash,  soda,  or  whatever 
may  be  used  as  accelerator,  being  varied  accordingly.  Compare  two  negatives,  after  the 
most  has  been  done  for  both,  according  to  their  requirements.  The  former  will  be  found 
to  be  highly  satisfactory  before  the  comparison  is  made,  and  will  yield  points  to  please  a 
certain  class  of  photographers,  and  also  their  customers.  It  might  be  said,  Where,  then, 
is  the  use  of  changing  ?  The  use  of  changing  would  be  to  make  photographs  represent- 
ing nature  more  perfectly  and  raise  the  standard  of  photography  in  comparison.  The 
latter  negative  will  be  found  to  possess  a  depth  of  richness  in  white  drapery,  and  the 
blackest  velvet  be  full  of  half-tone,  when  both  are  taken  together  on  the  one  negative, 
thus  representing  nature  to  perfection,  so  far  as  light  and  shade  can  do,  and  leaving  the 
best  results  of  the  wet  plate  a  thing  of  the  past.  I  am  well  aware  that  such  results  are 
not  got  every  day,  but  I  am  as  well  aware  they  have  been  and  ought  to  be,  and  with 
nothing  short  of  this  should  photographers  rest  content. 

I  have  changed  from  one  developer  to  another  until  at  present  I  am  most  in  love  with 
the  one  published  by  Mr.  Cooper  as  recommended  for  the  Eastman  plate. 

I  prefer  to  make  it  up  dilute  enough  at  once  to  use  equal  parts  without  having  to  go 
to  the  trouble  and  time  of  measuring  it  out  to  add  to  so  much  water. 

No.  1.  Pyro,  1  ounce;  sulphite  of  soda,  4  ounces;  hot  water,  48  ounces. 

No.  2.  Washing  soda,  4  ounces ;  hot  water,  48  ounces. 

Use  equal  parts  to  develop  with,  and  to  gain  more  density  add  a  drop  or  two  of  a  fifty 
grain  solution  of  bromide  of  ammonium.  Very  little  of  the  bromide  solution  will  make 
a  great  difference  in  the  action  of  this  developer.  A  little  longer  exposure  will  be  re- 
quired when  any  bromide  is  used.  If  a  plate  should  show  any  trace  of  fog,  lengthen  the 
exposure  and  use  less  of  the  soda  and  a  little  more  of  the  bromide ;  and  it  will  be  a  very 
bad  plate,  and  one  that  should  never  have  been  coated,  if  this  will  not  give  clear  nega- 
tives. I  would  recommend  keeping  the  developer  at  from  80°  to  90°  in  the  winter.  No 
fear  of  frill  or  softening  of  the  film. — JAMES  INGLIS. 

Overdeveloped  Negatives. — Almost  the  very  last  thing  that  a  photographer  learns,  is  the 
exact  point  at  which  to  stop  development.  It  is  easy  to  give  a  criterion  to  fix  the  point  ; 
the  difficulty  lies  in  acting  up  to  it.  To  get  the  most  perfect  combination  of  brilliancy 
and  softness,  one  should  develop  just  as  long  as  transparency  remains  in  those  denser 
portions  of  the  image,  which  are  to  constitute  the  high  lights,  so  that  the  very  central 
spot,  as  it  were,  of  the  highest  light,  shall  print  white.  But  then  this  must  be  a  mere 
point,  smaller  than  a  pin's  head.  Just  so  soon  as  this  point  widens  out  a  little,  we  get 
that  repulsive  chalkiness  that  leads  the  careful  photographer  to  consider  the  negative  as 
worthless.  (See  note  by  Eugene  Albert,  page  358.) 


NEGATIVE-MAKING  —  DRY.  363 

162.  One  of  the  great  obstacles  in  the  way  of  successful  emulsion  work  is 
frilling.  It  will  be  treated  of  presently.  One  method  of  preventing  it  is  to 

The  difficulty  in  hitting  the  right  point  lies,  not  merely  in  the  needful  experience  of 
what  the  negative  should  be,  but  in  judging  it  under  difficulties.  The  light  in  the 
operating-room  is  often  insufficient ;  but  even  if  abundant,  its  color  is  unfavorable,  and 
the  negative  itself  is  to  some  extent  blocked  up  by  the  undissolved  iodide  and  bromide. 
Besides,  the  fixing-bath  varies  in  strength,  and  acts  differently  upon  different  films,  so 
that  at  times  more,  and  at  others  less,  reduction  of  strength  occurs  in  the  fixing 

Experience  and  close  observation  remove  these  difficulties  to  a  large  extent,  but  not 
altogether,  so  that,  after  a  succession  of  good  results,  there  will  be,  from  time  to  time,  a 
negative  got  in  which  too  much  attempt  at  brilliancy  has  been  made,  and  which,  when 
viewed  after  fixing  and  by  ordinary  light,  gives  evidence  of  something  like  blockiness  in 
the  high  lights.  In  work  done  at  home,  it  will  generally  be  best  to  try  again.  But  even 
then,  the  discovery  may  come  too  late,  and,  in  views  exposed  at  a  distance,  we  have  not 
this  remedy,  and  in  either  case,  must  see  what  can  be  done  with  the  negative. 

I  take  it  that  a  careful  photographer,  when  such  mistakes  do  occur,  will  find  them  out 
before  he  varnishes  the  negative.  Not,  perhaps,  in  trying  new  methods,  or  in  working 
new  sorts  of  dry  plates,  in  which  often  the  actinic  transparency  and  opacity  are  very 
deceptive,  but,  in  any  regular  work  habitually  pursued,  the  exercised  eye  will  always 
detect  this  defect  before  varnishing.  If  not,  then  very  troublesome  operations  of  dark- 
ening parts  of  the  back  may  need  to  be  tried.  Varnish,  colored  yellow  with  alcohol, 
solution  of  annatto,  of  dragon's  blood,  or  of  gamboge,  may  be  tried,  perhaps,  with 
advantage,  though  the  writer  has  never  had  much  satisfaction  out  of  this  sort  of  opera- 
tion.—M.  CAREY  LEA,  M.D. 

162.  To  prevent  the  loosening  of  the  gelatine  film  in  the  fixing  bath,  which  happens 
very  easily  during  the  warm  weather  of  summer  time,  and  to  harden  the  film,  I  part  of 
hypo  solution  (1  to  4)  is  mixed  with  £  to  2  parts  of  saturated  aqueous  alum  solution. 
The  mixture  will  pretty  soon  "become  muddy  by  separation  of  sulphur  and  sulphurous 
acid,  but  for  all  that  it  acts  satisfactorily. 

The  negatives  easily  become  milky,  which  is  no  hindrance  in  their  printing  qualities; 
but  it  does  not  look  very  well,  and  is  the  reason  for  using  the  mixed  hypo  and  alum 
baths  only  in  exceptional  cases.  The  first  negatives  are  washed,  dried,  varnished,  and 
according  to  requirement  strengthened  or  reduced. — DR.  J.  M.  EDER. 

The  proper  use  of  the  alum  bath  in  connection  with  the  dry  plate  is  this:  When  the 
plate  is  fully  developed  wash  it  under  the  tap,  or  souse  it  in  a  dish  of  water;  wash  it 
well,  then  plunge  it  into  an  alum  bath  for  half  a  minute.  Why?  If  the  developer  goes 
over  into  the  hypo  a  little  on  each  plate  the  hypo  gets  stained,  and  in  the  dark-room  you 
can't  see  it,  and  then  the  film  on  the  plate  gets  stained;  the  washing  will  get  off  most  of 
the  developer,  and  the  alum  is  a  scavenger,  and  it  readily  picks  up  the  pyro  and  the 
alkali,  and  cleans  off  what  you  cannot  see,  but  what  will  show  in  the  bottom  of  the  alum 
bath,  very  prominently,  after  six  or  eight  plates  have  been  through;  then  wash  again, 
and  chuck  into  the  hypo ;  now  your  plate  will  not  "  cockle,  frill,"  or  run  off  the  hypo ; 
when  through  with  it,  it  can  be  washed  off  best  by  a  soak  of  five  minutes  in  still  water, 


364 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


immerse  the  plate  in  a  saturated  solution  of  alum  for  five  minutes  previous  to 

fixing  it.     The  negative  should  be  well  rinsed  before  and  after  this  operation. 

163.    Hyposulphite  of  soda  is  the  very  best   material  for   fixing.      The 

strength    should  be,  say,    four  ounces  of  hyposulphite  to  a  quart  of  water. 

and  then  back  into  the  alum  bath,  where  it  can  He  five  minutes  or  half  an  hour,  and 
then  let  it  go  to  the  wash  for  three  to  five  hours.  Don't  mix  the  developer  into  the 
alum ;  don't  mix  alum  and  hypo ;  don't  mix  hypo  and  alum ;  don't  carry  a  plate  from 
one  bath  into  any  other  without  well  washing  each  one  every  time. — THOMAS  PRAY,  JR. 

I  have  recently  made  some  experiments  with  solution  of  sal-ammoniac  as  a  medium 
for  the  fixing  of  bromide  of  silver  gelatine  plates.  Plates  which  had  been  exposed, 
when  subjected  to  the  action  of  the  bath  for  several  hours,  lost  completely  the  bromide 
of  silver  which  they  contained,  in  the  film,  and  merely  the  pure  gelatine  layer  appeared. 
The  effect  was  more  rapid  when  the  plates  were  first  treated  with  ammonia.  Plates 
which  had  been  developed  with  pyrogallic  acid  were  slower  in  fixing  under  the  influence 
of  the  sal-ammoniac  solution  than  unexposed  plates,  but  with  a  longer  time  the  fixing 
was  effectual.  Plates  containing  iodide  of  silver  in  the  film  in  connection  with  the  bro- 
mide of  silver  exhibited  a  trace  of  fogginess,  probably  from  the  unaffected  iodide  of  sil- 
ver which  did  not  injure  them  in  the  least,  and  which  entirely  disappeared  with  longer 
treatment  with  the  fixing  bath,  but  the  bromide  of  silver  plates  fix  perfectly  clear.  I 
have  not  perceived  in  our  experience  any  injurious  influence  of  the  sal-ammoniac  solu- 
tion upon  the  film  with  the  employment  of  plates  prepared  by  the  newer  method  with 
chrome  alum.  True,  the  plates  assume  in  the  bath 
a  strong  relief,  and  sometimes  worm-shaped  eleva- 
tions appear,  which,  however,  shrink  up  on  dry- 
ing, and  do  not  interfere  with  copying  or  in  making 
transparencies.  The  tone  of  the  picture  is  an 
agreeable  brownish-black.— DR.  E.  LIESEGANG. 

163.  Mr.  Henry,  of  Limoges,  describes  a  washer 
(Fig.  322)  for  gelatine  plates  for  which  the  follow- 
ing advantages  are  claimed: 

Any  thickness  of  glass  can  enter  the  grooves 
which  are  in  such  a  way  that  they  do  not  abrade 
the  gelatine  film.  The  water  is  divided  over  the 
whole  surface  of  the  box,  and  is  maintained  always 
at  the  same  level  by  means  of  a  siphon.  When 
the  pressure  of  water  is  very  variable,  and  when 
the  siphon  does  not  suffice,  a  device  is  used  to  avoid 
an  overflow.  Finally,  the  plates  may  be  removed 
with  the  greatest  care. 

Another  automatic  washer,  invented  by  Captain 
Gorcoix  (Fig.  323),  is  formed  of  a  waterproof  box 
in  which  is  suspended  a  metal  recipient  rendered  impermeable  by  means  of  bitumen  of 
Judea.     This  recipient  is  formed  of  two  triangular  or  prismatic  troughs  joined  by  one 


Fio.  822. 


NEGATIVE -MAKING  —  DRY. 


365 


Most  thorough  washing  should  follow  the  fixing  in  order  to  eliminate  every 
particle  of  hyposulphite  from  the  film. 

of  their  sides.  The  water  introduced  from  the  top  accumulates  in  one  of  the  troughs 
When  it  reaches  a  certain  level,  its  weight  brings  it  down  and  lifts  up  its  companion. 
This  water  runs  into  the  dish  loaded  with 
the  salts  to  be  diluted,  and  during  this  time 
the  other  trough  is  being  filled  in  its  turn 
to  obtain  the  inverse  motion.  There  can  be 
no  question  that  the  water  loaded  with  dele- 
terious substances  is  entirely  thrown  out  and 
renewed  at  each  rise  and  fall.  The  time 
of  contact  is  made  greater  or  less  by  regula- 
ting the  flow  of  water. 

The  staining  of  the  film  has  been  the  cause 
why  so  many  have  given  up  the  pyro  developer,  valuable  as  it  is  in  many  points,  and 
have  turned  to  the  oxalate.  But  the  advantages  of  the  pyro  cannot  be  had  by  using  any 
other  developer;  therefore  the  attempts  are  many  which  have  been  made  to  prevent  or 
remove  the  discoloration.  I  have  found  the  following  excellent: 

A  saturated  solution  of  alum,  500  c.  cm ;  citric  acid,  4  grammes ;  or,  instead  of  citric 
acid,  muriatic  acid  may  be  used.  Alum,  500  c.  cm.;  muriatic  acid,  30  c.  cm.  Wash  the 
negative  well  after  fixing  before  subjecting  it  to  the  clearing  solution. 

Another  good  clearer  is: 
Alum,  30  grammes;  citric 
acid,  30  grammes;  sulphate 
of  indigo,  90  grammes;  water, 
600gra  mmes. 

The  plates  need  only  be 
slightly  washed  after  fixing, 
and  allowed  to  lie  in  the  so- 
lution till  they  attain  a  beau- 
tiful brown  color.— R.  G. 
WEISS. 

The  pan  shown  (Fig.  324) 
is  intended  to  set  on  the  top 
of  an  ordinary  sink.  The 
water  runs  from  the  tap  into 
the  open  space  A,  thence  it 
flows  in  the  direction  of  the 
arrows  and  enters  the  pan 
through  small  holes  in  the 
bottom  of  the  partition  J5, 
flows  over  the  negative  C  to  the  partition  D,  when  it  flows  out  through  small  holes  in  the 
top  of  the  partition  in  the  channel  E,  and  running  out  of  the  pan  at  F  into  the  sink. 


FIG.  324. 


366        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

To  determine  certainly  when  this  is  effected  a  test  may  be  made  of  a  portion 
of  the  wash  water  as  directed  for  the  printing  department. 

The  water  flows  in  one  sheet,  without  eddies,  from  B  to  D.  This  can  be  easily  tested  by 
dropping  into  the  channel  A  some  soluble  aniline  color.  Plates  fresh  from  the  hypo 
are  put  near  the  end  Z>,  and  when  the  pan  is  full,  negative  C1  will  be  washed  enough  and 
can  be  removed  and  the  other  plates  shoved  up  to  make  room  for  the  next  plate  to  be 
developed.  If  desired,  alum  can  be  put  in  a  little  ridge  across  the  pan  between  C3  and 
(73 ;  it  will  be  gradually  dissolved  and  act  on  the  negative  toward  Z>,  but  those  on  the 
other  side  will  not  be  affected;  or  the  alum  can  be  put  in  the  channel  A. 
~  I  will  give  the  actual  dimensions  of  my  pan,  and  from  that  others  can  judge  what  size 
will  best  suit  their  wants.  I  use  plates  8  x  10,  6 $•  x  8|,  and  4£  x  6£.  The  pan  I  have  is 
nine  inches  wide  where  the  plates  lay  and  thirty-six  inches  long.  The  sides  are  one  and 
a  half  inches  high ;  the  partition  walls  B  and  D  are  one  and  a  quarter  inches  high. 
Partition  B  has  sixteen  holes  one-eighth  inch  diameter,  and  as  close  to  the  bottom  as 
possible.  Partition  D  has  the  same  number  and  size  of  holes  seven-eighths  of  an  inch 
from  the  bottom.  The  channels  A  and  J^are  one  inch  wide.  The  outlet  Fis  one-half 
inch  diameter.  The  pan  is  made  of  copper,  with  a  very  heavy  wire  around  the  edge. 
There  are  four  ridges  running  the  whole  length  of  the  bottom,  -fa  inch  high,  to  keep  the 
plates  up  a  little.  The  outlet  F  is  brought  close  to  the  inlet  A  so  that  it  can  be  placed 
in  any  direction  on  a  common  sink.  The  holes  in  partition  B  are  placed  close  to  the 
bottom  to  prevent  eddies.— O.  W.  HUNT. 

I  made  a  fixing  tray  which  I  like  so  well  that  I  think  some  of  your  readers  may  like 
to  get  one  of  the  same  kind. 

The  tray  is  8?  x  10J  inches  inside,  and  3£  inches  deep,  made  of  £-inch  boards.    The 
bottom  is  only  2£  inches  wide,  but  spreads  out  until  8£  inches  apart  about  2i  inches  from 

the  lowest  part  of  the  bottom, 

325>  and  then  the  sides  go  straight 

up  (Fig.  325). 

The  negatives  are  fixed  with 
the  film  side  down,  and  they 
come  out  clean,  even  if  the  bath 
is  very  old  and  discolored,  and 
besides  many  negatives  can  be 
fixed  at  the  same  time. 

I  use  a  tray  of  the  same  shape 
for  washing  negatives,  and  to  this 
I  have  added  a  practical  siphon 

(Fig.  326).  This  is  made  out  of  a  piece  of  wood  1}  inch  wide,  f  inch  thick,  and  £  inch 
shorter  than  the  tray  is  deep ;  from  this  is  cut  out  a  piece  lengthways,  so  that  it  will 
leave  a  hole  about  \  inch  in  diameter,  when  the  piece  is  nailed  to  the  inside  of  the  end 
of  the  tray,  and  there  is  left  an  opening  of  about  \  an  inch  at  the  bottom  to  let  the  water 
in.  At  the  top  there  is  bored  a  hole  through  the  tray  to  let  the  water  out,  but  so  high 
up  that  it  will  leave  three  inches  of  water  in  the  tray. 


NEGATIVE- MA  KING  —  DRY. 


367 


If  after-treatment  is  needed,  when  the  plates  are  perfectly  dried,  they  may 
be  varnished,  as  directed  for  the  wet. 

The  negatives  are  washed  with  the  film  side  down,  and  may  be  left  in  the  water  many 
days  without  any  injury.     As  the  plates  only  rest  on  two  ends,  many  plates  may  be 
washed  at  the  same  time  without  one 
touching  the  other,  and  I  think  the 
washing  goes  on  quicker  than  when  the 
negatives  are  left  with  the  film  up. 

I  make  the  end  pieces  square,  so 
that  the  trays  will  have  a  good  base  to 
stand  on.  The  same  kind  of  siphon  ienigiHBBiM 
can  very  successfully  be  used  on  wash- 
ing tray  for  paper  prints.  I  paint  the 
trays  with  asphaltum  varnish. — J.  J. 
ESKIL. 

A  negative- washer  that  you  can  make 
yourself.  Take  a  piece  of  zinc  and 
bend  it  in  shape  of  an  old-fashioned 
pig  trough  any  length  you  want  it, 

stop  up  one  end  and  put  the  other  in  the  sink ;  take  a  piece  of  lead-pipe  a  little  shorter, 
and  make  holes  about  one  inch  apart,  and  hang  over  it,  and  connect  the  water  with  a 

rubber  hose;   you  thus  have  the  best  washer 

FIG  327.  that  can  be  made.    Lay  the  plates  across  the 

trough,  and,  of  course,  the  smaller  ones  will 
go  nearer  the  bottom,  and  the  larger  ones  near 
the  top,  or  you  can  wash  two  or  three  layers  of 
plates  at  one  time  if  necessary.  Fig.  327. — C. 
H.  SCOFIELD. 

When  is  the  hypo  out  of  gelatine  negatives  ? 
I  have  for  guide,  viz.,  plates  that  develop  and 
fix  quick,  hypo  washes  out  of  quickly.  Plates 
slow  in  developing,  and  very  slow  in  fixing, 

will  be  very  slow  in  having  the  hypo  washed  out — in  fact,  with  such  plates  one  is  never 
sure  that  the  hypo  is  ever  got  rid  of.  Such  plates  give  up  the  hypo  better  by  soaking 
than  being  washed  directly  under  the  tap.  Hypo  in  gelatine  negatives  is  not  so  destruc- 
tive as  in  collodion,  but  finally,  will  destroy  them/  I  have  negatives,  gelatine,  five 
years  old,  that  have  hypo  in  them,  and  yet  are  used  to  produce  good  prints  from  them. 
The  test  whether  hypo  is  out  of  any  gelatine  negative,  take  a  plate  that  has  been 
given  the  supposed  washing  to  rid  it  of  hypo,  put  it  on  a  levelling  stand,  cover  it  with 
water,  let  it  remain  there  some  twenty  minutes,  now  pour  this  water  into  a  weak  solu- 
tion of  bichloride  of  mercury ;  if  a  precipitate  is  produced  the  plate  has  not  been  suf- 
ficiently washed ;  if  the  mercury  solution  remains  clear,  one  can  be  reasonably  sure  that 
the  hypo  is  out. — WM.  BELL. 


368        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

164.  When  the  manufacture  of  bromo-gelatine  emulsion  plates  was  taken 
up  in  earnest,  a  great  many  stumbling  blocks  were  found  in  the  way.  Some 
of  the  difficulties  seemed  insurmountable.  Those  who  partially  overcame  them, 

I  believe  that  by  placing  the  plates  in  a  bath  of  weak  javelle  water,  say  a  tablespoon- 
ful  in  a  quart  of  water,  it  is  possible  to  eliminate  the  last  trace  of  hyposulphite.  Care 
must  be  taken  not  to  use  too  much  of  the  javelle  water,  as  in  this  case  the  negative  might 
be  injured;  many  operators  only  use  a  teaspoonful  in  a  quart  of  water.  If  the  plate  has 
been  well  washed,  twenty  drops  will  suffice.  There  exists  a  solution  of  Labarraque  for 
washing,  containing  dry  chloride  of  lime,  which  acts  in  the  same  manner  as  the  solution 
of  javelle  water ;  its  eifect  is  almost  instantaneous.  Here  is  the  way  of  making  this 
solution : 

Preparation  of  the  Solution  of  Javelle  Water. — Dissolve  four  ounces  of  dry  chloride  of 
lime  in  a  quart  of  water ;  close  well  the  bottle  and  shake  from  time  to  time.  In  another 
vessel  dissolve  four  ounces  of  dry  common  potash  in  a  quart  of  water ;  allow  these  two 
solutions  to  rest  from  six  to  ten  hours,  then  slowly  pour  the  potash  solution  into  that  of 
the  chloride  of  lime,  agitating  the  vessel  evenly.  Allow  the  mixture  to  repose  for  a  half- 
hour,  then  filter  through  paper;  the  product  obtained  is  a  pure  javelle  water,  which,  in 
a  well-stoppered  bottle,  and  kept  in  a  cool  place,  will  not  deteriorate.  In  using,  before 
taking  the  prints  from  the  hyposulphite  baths,  pour  in  three  quarts  of  water,  as  many 
times  five  and  a  half  fluiddrachms  of  the  solution  as  there  are  prints  in  the  fixing  bath. 
The  prints  taken  from  the  hyposulphite  baths  are  carefully  drained  and  gently  placed  in 
the  javelle  water,  in  which  they  are  allowed  to  remain  three  minutes,  keeping  them  con- 
stantly in  motion;  after  which  the  bath  is  again  renewed  for  three  minutes.  The  prints, 
well  rinsed,  are  now  ready  to  be  mounted. — LEON  VIDAL. 

164.  The  IVilson-Paget  Prize  Emulsion. — Proceed  as  follows :  To  make  a  pint  of  emul- 
sion :  Select  a  20-ounce  narrow  mouth  stoppered  bottle,  with  a  well-fitting  stopper  and 
thin  bottom.  Make  it  perfectly  clean.  Make  a  stock  solution  of  hydrochloric  acid 
(pure),  1  fluiddrachm;  distilled  water,  12£  ounces.  Put  into  the  20-ounce  bottle  20 
minims  of  the  above  dilute  acid;  3  fluidounces  distilled  water;  210  grains  dry  ammo- 
nium bromide;  80  grains  Nelson's  No.  1  photo,  gelatine.  Leave  the  gelatine  to  swell 
for  (say)  fifteen  minutes  or  longer. 

The  addition  of  a  trace  of  hydrochloric  acid  to  the  soluble  bromide  and  gelatine  is  recom- 
mended in  the  formula  given  for  the  following  reasons :  If  the  soluble  bromide  be  abso- 
lutely neutral,  and  the  gelatine  a  suitable  sample,  the  hydrochloric  acid  is  not  necessary, 
and  better  omitted.  If,  however,  the  gelatine  be  ever  so  little  alkaline,  or  even  appa- 
rently neutral,  but  yet  does  not  give  a  clear  solution,  acid  is  required.  Its  use  is  not  to 
produce  silver  chloride,  but  to  insure  a  fine  precipitate  of  silver  bromide.  A  fine  precipi- 
tate is  easily  obtained,  however  rapidly  the  solutions  be  mixed,  if  two  conditions  exist, 
viz.,  if  the  bromized  gelatine  solution  contain  a  trace  of  hydrochloric  acid,  and  the  silver 
solution  be  not  stronger  than  110  grains-  per  ounce.  If  it  be  50  to  60  grains  per  ounce? 
it.may'be  all  poured  in  at  once  ;  or  if  a  little  weak  solution  be  first  poured  in,  the  stronger 
may  follow  (as  per  formula).  A  good  test  for  the  suitability  of  a  gelatine  is  to  see  if  a 
fine  precipitate  can  be  obtained  without  having  to  add  hydrochloric  acid.  Too  much 


NEGATIVE-MAKING  —  DKY.  369 

although  they  owed  the  most  of  what  they  knew  to  the  industry  of  others, 
withheld  their  own  "finds"  rather  ungenerously. 

hydrochloric  acid  retards  or  prevents  the  conversion  of  the  silver  bromide  into  the  sensi- 
tive form  in  cooking ;  a  large  excess  destroys  the  gelatine. 

The  addition  of  hydrochloric  acid  must  be  made  intelligently,  according  to  the  other 
materials  accessible. 

Ammonium  bromide  should  be  as  nearly  as  possible  neutral.  It  is  usually  more  or  less 
acid,  even  though  otherwise  pure,  and  frequently  becomes  strongly  acid  by  keeping.  It 
is  then  unfit  for  use,  and  will  not  give  good  results  unless  almost  neutral. 

On  the  whole,  it  is  better  to  use  bromide  of  potassium.  The  latter  is  often  alkaline, 
but  may,  without  much  difficulty,  be  obtained  neutral,  and  is  free  from  any  tendency  to 
alter. 

Silver  nitrate  is  usually,  if  good,  slightly  acid  with  excess  of  nitric  acid.  It  may  be  so 
used ;  but  better  results  are  obtained  if  the  silver  solution  be  neutralized  with  carbonate 
of  soda.  A  slight  excess  does  no  harm,  as  the  resulting  trace  of  carbonate  of  silver  is 
converted  into  bromide ;  indeed,  an  emulsion  may  be  made  by  mixing  washed  carbonate 
of  silver  with  a  soluble  bromide. 

The  uses  of  neutralizing  the  silver  are  twofold.  One  is,  that  as  the  amount  of  acidity 
of  silver  nitrate  varies  with  different  samples,  it  insures  the  same  conditions  in  all  cases; 
the  other  is,  that  the  presence  of  nitric  acid  in  an  emulsion  produces  a  tendency  to  green 
and  pink  discoloration  in  the  finished  negative. 

In  another  clean  glass  vessel  (beaker,  measure,  or  flask)  dissolve  330  grains  of  nitrate 
of  silver  (recrystallized)  in  three  ounces  distilled  water. 

Pour  out  about  two  drachms  of  this  silver  solution  into  another  small  vessel  (say  a  test 
tube),  and  dilute  it  to  half  strength  with  an  equal  quantity  of  distilled  water. 

Take  the  20-ounce  bottle  and  the  two  lots  of  silver  solution  into  the  dark  room.  The 
writer  prefers  to  use  a  large  paraffine  lamp  protected  by  one  thickness  of  ruby  and  one 
of  dark  orange  glass,  to  two  thicknesses  of  dark  orange  paper  without  any  ruby. 

In  the  dark-room  have  a  gas  boiling  stove,  and  on  it  a  tin  pot  or  saucepan  deep 
enough  to  contain  the  bottle  when  the  lid  is  on.  It  should  have  a  perforated  tin  false 
bottom,  to  prevent  the  bottle  resting  immediately  on  the  true  bottom ;  or  a  piece  of 
wire  gauze  will  answer.  Let  the  pot  contain  some  three  or  four  inches  in  depth  of 
boiling  water. 

Turn  out  the  gas  of  the  stove  if  alight,  and  plunge  the  bottle  into  the  water  two  or 
three  times,  so  as  to  avoid  cracking  it  by  too  sudden  heating ;  then  leave  it  for  a  few 
minutes,  until  the  gelatine  is  completely  dissolved.  Do  not  leave  it  in  longer  than  neces- 
sary for  complete  solution.  Take  it  out,  shake  up,  remove  the  stopper,  and  set  bottle 
down  on  table  near  your  lamp,  so  that  you  can  see  what  you  are  doing. 

Pour  in,  all  at  once,  the  four  drachms  of  dilute  silver  solution.  Put  in  the  stopper  and 
shake  up  thoroughly,  but  not  too  violently,  for  about  half  a  minute.  Now  pour  in  the 
strong  silver  solution  in  quantities  of  about  half  an  ounce  at  a  time,  shaking  as  before 
after  each  addition,  and,  when  all  is  added  give  a  final  thorough  shaking  for  (say)  a 
couple  of  minutes. 

24 


370        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

This  induced  Mr.  Paget  to  offer  a  prize  for  the  best  workable  emulsion 
method  given  free  to  the  public.  The  prize  was  won  by  Mr.  W.  Wilson,  of 
London,  and  his  process  is  given  below  entire. 

If  the  instructions  have  been  so  far  accurately  followed,  there  will  be  no  coarse  precipitate  or 
grit  in  the  finished  emulsion. 

Now  put  the  bottle  into  the  pot  of  hot  water,  see  that  the  stopper  is  not  jammed  in, 
and  put  on  the  lid.  Light  the  gas,  and  boil  up  as  quickly  as  possible.  If  the  water  was 
previously  boiling,  and  the  gas  only  turned  out  for  the  mixing  operation,  it  should  boil 
up  in  less  than  five  minutes ;  then  keep  boiling  for  fifty-Jive  minutes.  At  the  end  of  this 
time  turn  out  the  gas,  take  off  the  lid,  take  out  the  bottle,  and  remove  the  stopper  at 
once,  or  you  will  not  get  it  out  afterward.  The  bottle  must  now  be  cooled  down  as 
quickly  as  is  consistent  with  safety  to  the  glass.  In  very  cold  weather  it  may  stand  on 
the  table  for  ten  minutes  or  so,  and  then  be  cooled  with  water ;  or,  in  any  weather,  place 
it  in  a  pan  of  nearly  boiling  water,  and  cool  gradually  by  allowing  cold  water  to  trickle 
slowly  in,  shaking  the  bottle  occasionally.  Whatever  method  is  adopted,  it  should  be 
down  to  90°  F.,  or  lower,  in  fifteen  or  twenty  minutes  at  most.  It  cannot  easily  be  made 
too  cold,  as  the  gelatine  has  lost  its  power  of  setting. 

In  a  glass  beaker  (about  12  or  14  ounce  size)  put  one  ounce  of  Nelson's  No.  1  photo. 
or  "X  opaque"  gelatine,  and  pour  over  it  10  ounces  of  clean  ordinary  water.  Leave  it 
to  soak  until  the  gelatine  has  absorbed  4  ounces  of  water,  pour  off  the  surplus  6  ounces, 
melt  the  swelled  gelatine  by  immersing  the  beaker  in  hot  water,  and  pour  it  into  the  20- 
ounce  bottle  containing  the  cooled  emulsion.  Shake  up  well,  and  pour  all  back  into  the 
beaker,  draining  out  the  bottle  thoroughly.  Leave  it  to  settle  in  a  cool  place  for  twenty- 
four  hours.  It  must  next  be  washed. 

The  addition  of  the  gelatine  after  boiling  should  be  made  when  the  boiled  emulsion 
and  dissolved  gelatine  are  both  at  as  low  a  temperature  as  possible,  and  between  the  time 
of  this  addition  and  that  of  washing  the  emulsion  it  should  be  kept  as  cold  as  possible. 
The  reason  of  this  appears  to  be  that  the  excess  of  alkaline  bromide  has  a  most  destruc- 
tive effect  on  the  new  gelatine,  and  therefore  the  lower  the  temperature  and  shorter  the 
time  during  which  the  two  are  in  contact  the  better. 

There  is  a  curious  effect  depending  on  the  temperature  at  which  the  emulsion  and 
fresh  gelatine  are  mixed,  viz.,  that  if  quite  cold  the  resulting  plate  will  have  a  matt  sur- 
face, and  the  higher  the  temperature,  the  more  glossy  it  will  be. 

A  plain  solution  of  gelatine  in  pure  water  is  very  little  injured  by  prolonged  boiling; 
but  if  an  alkaline  bromide  (or  chloride)  be  added,  it  is  speedily  decomposed.  Probably 
the  alkaline  nitrate,  which  is  present  in  the  emulsion  in  large  quantity,  may  be  even 
more  effective. 

For  the  washing,  clean  ordinary  water  at  a  temperature  not  over  50°  should  be  used. 
Water  cooled  down  to  below  40°,  by  melting  ice  in  it,  gives  uniform  results. 

In  a  glazed  earthenware  pan  or  other  suitable  vessel  put  about  3  pints  of  cold  water, 
and  add  3  ounces  of  saturated  solution  of  bichromate  of  potash  (made  by  saturating  clean 
ordinary  water  with  recrystallized  bichromate). 

Before  squeezing  the  set  emulsion  through  the  canvas,  it  should  be  cooled  down  so  as 


NEGATIVE-MAKING  —  DRY.  371 

165.  Still  there  were  drawbacks,  one  of  the  greatest  being  the  impossibility 
of  securing  a  satisfactory  degree  of  sensitiveness  without  weak,  insipid  results. 

to  be  as  firm  as  possible.  If  so,  the  water  into  which  it  is  squeezed  remains  almost  clear, 
or  but  slightly  milky.  If  the  emulsion  be  soft,  even  though  the  water  be  ice  cold,  the 
water  will  be  more  milky,  and  the  emulsion  take  up  too  much.  Too  much  excess  of  said 
bromide,  too  high  a  temperature  at  the  time  of  adding  the  gelatine,  or  keeping  at  too 
high  a  temperature  between  adding  and  washing,  will  produce  the  same  result. 

The  emulsion  may,  of  course,  be  washed  by  precipitating  with  alcohol,  squeezing  the 
clot,  breaking  it  up,  and  soaking  in  water;  but  the  writer  prefers  washing  with  water 
and  bichromate,  as  described,  on  account  of  the  clear  and  brilliant  shadows  so  obtained. 

Having  cooled  the  beaker  of  set  emulsion  down  to  40°  F.,  run  a  bone  spatula  or  paper 
knife  round,  and  turn  out  the  emulsion,  or  cut  it  out  in  lumps.  If  cold,  it  wijl  come  out 
almost  or  quite  clean  from  the  glass.  Place  it  on  a  piece  of  coarse  "  straining  cloth,"  or 
canvas,  and  squeeze  through  the  meshes  into  the  water,  the  operation  being  performed 
under  the  surface  of  the  water.  Leave  it  for  an  hour.  Lay  the  straining  cloth  over  the 
mouth  of  another  pan  or  large  jar,  and  pour  the  mixture  of  emulsion  threads  and  liquids 
on  to  it,  so  as  to  let  the  latter  run  through.  Squeeze  the  emulsion  a  second  time  through 
the  cloth  into  clean  cold  water,  and  immediately  repeat  the  operation  a  third  time, 
leaving  the  emulsion  in  the  last  water  for  half  an  hour.  When  strained  for  the  last  time 
place  cloth  and  all  in  a  large  beaker,  and  put  the  latter  into  hot  water  until  the  emulsion 
is  completely  melted  and  warmed  to  about  115°  F. — i.  e.,  not  warmer  than  is  pleasant  to 
the  hand.  With  clean  hands  take  out  the  cloth  and  squeeze  it ;  very  little  will  be  lost. 
The  emulsion  should  now  measure  about  16  or  17  ounces.  Add  two  ounces  of  alcohol, 
and  mix  thoroughly.  The  alcohol  may  be  either  pure  methylic  alcohol,  sp.  gr.  about 
0.830,  or  good  colorless  methylated.  The  writer  prefers  the  former.  If  the  emulsion  now 
measures  less  than  20  ounces,  make  it  up  to  that  by  adding  clean  water. 

A  good  deal  depends  on  the  temperature  to  which  this  is  done,  and  by  careful  man- 
agement much  may  be  effected.  If  the  emulsion  is  sufficiently  rapid,  and  free  from  pink 
and  green  disease,  it  is  best  melted  and  coated  at  a  low  temperature.  If  it  be  slow  and 
has  a  tendency  to  color,  it  will  be  improved  by  heating  to  140°  F.  Some  emulsions  have 
became  more  than  three  times  as  rapid  by  this  treatment;  but  it  is  a  somewhat  more  dan- 
gerous one,  as  too  high  a  temperature  or  prolonged  heating  may  result  in  hopeless  gray 
fog,  which  is  more  apparent  during  the  development  than  after  fixing. 

The  emulsion  is  now  ready  for  use.  It  should  be  filtered  into  the  coating  cup  through 
cotton  wool  to  free  from  bubbles,  and  plates  coated  in  the  usual  way,  dried  and  used  as 
usual  for  rapid  gelatine  plates,  using  about  an  ounce  of  emulsion  for  a  dozen  quarter 
plates. 

In  drying  arrangements  avoid  the  contact  of  gas  or  of  the  products  of  the  combustion 
of  gas  with  the  moist  plates.  Both  are  very  injurious. — W.  WILSON. 

165.  Obernetter's  New  Emulsion  Method. — To  make  1  quart  (1  litre)  of  emulsion  put  2  drs. 
34  grs.  (10  grammes)  of  crystallized  soda  and  2  drs.  3.5  grs.  (8  grammes)  of  citric  acid 
with  3  oz.  1  dr.  43  minims  (100  grammes)  of  distilled  water  into  a  two  litre  (£  gallon) 
flask ;  heat  gently  until  the  salts  are  dissolved  and  effervescence  ceases  (five  minutes), 


372        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Mr.  J.  B.  Obernetter,  of  Munich,  claimed  to  have  overcome  this  trial,  and 
announced  his  readiness  to  sell  his  secrets  to  the  public,  provided  a  certain  sum 

and  add  1  oz.  4  drs.  52.5  grs.  (50  grammes)  of  gelatine  with  1  pint  (500  grammes)  dis- 
tilled water.  Let  the  gelatine  soak  for  half  an  hour  and  place  the  flask  in  hot  water 
until  the  gelatine  is  dissolved  (fifteen  minutes).  Meanwhile  dissolve  3  oz.  1  dr.  48  grs. 
( 100  grammes)  of  nitrate  of  silver  in  6  oz.  3  drs.  23  minims  (200  grammes)  of  distilled 
water,  add  it  to  the  warm  solution  of  gelatine,  and  also  1  oz.  4  drs.  5  minims  (50 
grammes)  distilled  water  with  which  the  vessel  containing  the  silver  solution  has  been 
washed.  The  mixture  will  become  milky.  After  being  shaken  well,  it  is  filtered  still 
warm  through  moistened  flannel  into  a  flat  dish  of  glass  or  porcelain,  or  into  several 
china  plates,  on  which  the  liquid  should  not  stand  higher  than  0.8-1.2  inches  (2-3  centi- 
metres). Cover  the  vessels  and  keep  them  guarded  against  direct  light  in  a  cool  place, 
between  43°  to  68°  F.  In  2  to  6  hours,  or,  still  better,  in  12  hours,  the  solution  will  have 
become  a  gelatinous  mass.  Cut  this  with  a  horn-spatula  into  slices  of  two-fifths  to  four- 
fifths  inches  in  diameter,  any  desirable  length,  and  throw  them  into  a  beaker  of  3  quarts 
(3  litres)  capacity.  Place  it  immediately  into  the  washing  apparatus  in  a  dark-room, 
and  pour  upon  it  a  solution  of  5  drs.  8  grs.  (30  grammes)  of  crystallized  soda  and  3  oz. 
1  dr.  43  grs.  (100  grammes)  of  bromide  of  ammonium  dissolved  in  1  pint  (500  grammes)  of 
distilled  water.  The  mixture  should  be  stirred  well  together  with  the  glass  tube  of  the 
washing  apparatus,  which  stirring  ought  to  be  repeated  every  half  hour  during  the  first 
two  hours.  The  longer  the  gelatinous  mass  is  exposed  to  the  action  of  this  solution,  the 
greater  will  be  the  sensitiveness  of  the  emulsion.  The  silver  salt  will  be  converted 
during  this  time  into  bromide  of  silver,  and  it  is  easy  to  become  aware  of  the  progress  of 
this  conversion  by  cutting  a  small  piece  of  the  gelatine  in  daylight. 

Six  hours  are  sufiicient,  although  I  continue  the  contact  over  night,  twelve  to  eighteen 
hours ;  greater  sensitiveness  is  superfluous,  if  not  injurious.  In  order  to  interrupt  the 
operation,  let  the  water  run  through  the  washing  apparatus,  for  which  twelve  hour^ 
suffice ;  but  I  wash  with  frequent  stirring  for  twenty-four  hours,  large  quantities  even 
forty-eight  to  sixty  hours — rather  wash  too  much  than  not  enough.  After  the  washing, 
let  the  water  run,  for  the  emulsion  is  done.  For  immediate  use,  melt  the  slices  at  122°  F., 
add  for  each  100  parts  of  emulsion  5  parts  of  alcohol  and  2-5  parts  of  albumen,  and 
filter  through  moistened  flannel ;  otherwise  the  emulsion  slices  are  preserved  in  alcohol 
of  80  per  cent.  Tralles. 

The  sensitiveness  is  increased  with  the  increase  of  the  proportion  of  soda,  which  ought 
not  to  exceed,  however,  double  the  weight  of  the  citric  acid. 

The  hardness  is  increased  by  the  decrease  of  the  soda  in  the  bromine  solution ;  it  should 
not  be  less  than  one-fifth  of  the  proportion  proposed. 

The  emulsion  will  work  softer  either  by  greater  sensitiveness  or  by  attenuation  of  the 
bromide  solution  with  water,  in  which  case  not  more  than  double  the  quantity  prescribed 
should  be  used. 

So  many  questions  have  arisen  concerning  the  method  employed  in  the  preparation  of 
•my  emulsion,  that  I  deem  it  advisable  to  sum  up  the  complaints  made,  to  determine  the 
causes  of  failures  and  furnish  the  means  of  preventing  them,  in  this  paper. 


NEGATIVE-MAKING  —  DRY.  373 

was  subscribed  for  him.  An  effort  to  obtain  subscribers  here,  resulted  in  the 
method  being  presented  to  the  public  by  the  late  John  A.  Scholten,  Esq.,  of 
St.  Louis. 

Fogging  of  the  Plate. — Here  the  camera  or  the  plate-holder  is  solely  to  blame ;  there 
may  be  an  imperceptible  leak,  or  the  dark-room  may  not  be  light-tight.  The  operation 
up  to  bromizing  may  be  carried  on  in  broad  daylight ;  with  the  remainder  a  low-turned- 
down  lamp  must  be  used. 

I  must  specially  caution  the  operator  when  flowing  the  plate,  on  thorough  setting. 
Then  the  plate  is  ready  for  exposure. 

When  the  developer  has  completely  covered  the  plate,  the  operation  may  be  carried 
on  very  comfortably  with  the  ordinary  yellow  light. 

The  emulsion  works  so  clearly  that  ferrotype  plates  prepared  theiewith,  after  fixing 
and  washing  for  two  minutes  in  the  mercury  preparation  recommended  by  me,  gave 
direct  positives  not  inferior  in  merit  to  collodion  pictures  of  this  kind.  Their  durability 
is,  however,  doubtful. 

The  Negative  is  Too  Thin. — This  fault  has  several  causes : 

(a)  The  plates  have  been  too  thinly  coated ;  one  cubic  centimetre  of  emulsion  to 
fifteen  centimetres  of  glass  is  proper. 

(b)  Using  stale  albumen.     The  albumen  is  designed  to  thicken  the  emulsion,  in  order 
to  hold  the  bromide  of  silver  easier  in  suspension.     It  also  has  a  beneficial  action  upon 
the  beauty  of  the  plate. 

(c)  In  the  earlier  preparations,  I  made  use  of  a  variety  of  Simeon's  gelatine,  which 
was  totally  useless  for  the  purpose,  giving  almost  no  image.     But,  to  do  justice  to  this 
gentleman,  I  must  add  that  the  samples  of  gelatine  he  has  recently  sent  me  are  excellent 
for  my  purpose.     I,  however,  prefer  for  general  use  Heinrich's  gelatine,  regarding  it  as 
the  surest. 

(d)  There  are  varieties  of  oxalate  of  potassa  which  are  cheap,  but  impure  and  acid; 
such  a  salt  gives  pictures  having  only  one  shade.     If,  however,  the  salt  be  used  only  in 
quantities  absolutely  necessary  to  dissolve  the  precipitate  of  ferro-oxalate  (two  volumes), 
one  volume  of  iron  solution,  vigorous  negatives  will  result. 

It  is  asserted  from  one  quarter  that  my  emulsion  washed  with  soft  water  gives  flat 
negatives,  but  with  hard  water  those  of  the  proper  strength.  I  dispute  this  assertion, 
but  shall  make  it  a  subject  of  investigation.  Should  such  be  the  case,  all  that  is  neces- 
sary is  to  harden  the  soft  water  by  a  piece  of  gypsum. 

The  Emulsion  Lacks  Sensitiveness. — The  sensitiveness  of  my  emulsion  in  comparison 
with  Dr.  Von  Monckhoven's  is  as  18  to  14;  in  comparison  with  English  emulsions,  it  is 
more  sensitive.  If  with  proper  illumination  the  lights  and  shadows  are  not  clearly 
indicated,  the  failure  may  be  traced  to  No.  2.  Or  the  cause  may  be  that  the  place  was 
too  cold  wherein  the  bromizing,  washing,  and  development  took  place.  To  the  question 
whether  my  method  furnishes  emulsions  which  have  the  same  sensitiveness  as  English 
plates,  I  leave  the  method  of  preparation  serve  as  an  answer,  which  rests  upon  known 
effects,  but  which  renders  possible  any  degree  of  sensitiveness. 

I  make  use  of,  for  this  purpose,  an  emulsion  which  has  soaked  .or  some  days  in  alcohol 


374         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Both  of  the  methods  named  were  published  in  the  Philadelphia  Photog- 
rapher at  the  time  of  their  being  made  public. 

— that  is,  one  from  which  much  of  the  water  has  been  extracted.  I  wash  it  with  common 
water  to  take  away  the  alcohol  upon  the  surface,  put  it  in  a  suitable  vessel,  and  melt 
the  emulsion  by  means  of  a  water-bath  at  about  70°  R.  When  the  emulsion  has  attained 
this  temperature,  I  add  to  every  one  hundred  grammes  of  emulsion  four  grammes  of 
bromide  of  potassium  and  a  quarter  of  a  gramme  of  iodide  of  potassium,  dissolved  in  a 
little  water,  and  after  frequent  agitation  suffer  it  to  stand  for  fifteen  or  thirty  minutes. 

A  trial  plate  may  be  flowed  and  examined  through  a  light  till  the  degree  of  sensitive- 
ness desired  is  attained,  but  the  experiment  should  go  no  further  when  the  light  trans- 
mitted is  of  gray  color  ;  twenty  minutes  are  sufficient.  The  bulb  containing  the  emulsion 
is  then  transferred  to  a  vessel  of  cold  water,  and  cooled  down  to  a  temperature  bearable 
to  the  hand.  To  every  one  hundred  grammes  of  emulsion  two-thirds  of  a  cubic  centi- 
metre of  spirits  of  ammonia  are  added,  the  whole  well  shaken  together,  and  then  poured 
out  upon  a  flat  dish  to  set,  which  takes  place  in  one  or  two  hours ;  it  is  then  cut  in  strips 
and  washed  in  the  apparatus  for  six  or  twelve  hours. 

The  emulsion  is  sensitive  to  the  highest  degree.  A  mixture  of  this  highly  sensitive 
emulsion  with  a  normal  emulsion  is  recommended;  it  is  preserved  under  alcohol  as 
readily  as  the  other. 

My  experiments  upon  the  subject  I  will  make  known,  and  I  desire  further  communi- 
cations of  the  results  of  others  in  the  matter. 

Some  Remarks  Concerning  the  Preparation  of  Emulsion. — Two  properties  of  the  bromide 
of  silver  emulsion  increase  its  value  to  photographers :  First,  the  unsurpassable  beauty 
of  the  negative  combined  with  purity.  Second,  its  high  sensitiveness  to  the  influence 
of  light. 

I  have  tried  to  combine  both  these  properties  in  a  method  at  once  simple  and  effective, 
famishing,  above  all,  negatives  entirely  free  from  fog.  The  sensitiveness  of  this  prepa- 
ration is  such  that  in  good  light,  although  the  sun  be  not  shining,  an  instantaneous 
exposure  is  sufficient  to  insure  the  best  results.  Nevertheless,  I  have  the  means  of 
increasing  this  sensitiveness  twofold,  but  the  labor  and  difficulties  attending  are  neces- 
sarily increased  fourfold,  the  light  employed  in  the  preparation  being  reduced  to  a 
minimum. 

The  limit  of  proper  time  of  exposure  is  difficult  to  determine ;  complete  success  in  this 
respect  is  only  attained  by  practice. 

I  have  found  it  highly  advantageous  to  combine  emulsions  prepared  by  different 
methods,  those  which  are  highly  sensitive  and  easy-working,  and  those  which  are  less 
sensitive  and  which  do  not  work  so  easily. 

The  following  formula  gives  an  emulsion  which  is  characterized  by  precision  in  mode 
of  operating — that  is,  it  can  be  employed  equally  well  in  reproducing  an  engraving  by 
Diirer  as  well  as  an  oil  painting  or  portrait.  It  furnishes  perfect  negatives  with  ease  of 
manipulation.  I  subjoin  some  remarks  concerning  the  preparation,  the  apparatus  em- 
ployed, and  the  mode  of  operation. 

Albumen. — By  albumen,  I  mean  pure  albumen  obtained  by  beating  the  whites  of  hen's 
eggs,  fresh  and  free  from  all  yolk,  to  a  stiff  froth  and  allowing  it  to  subside. 


NEGATIVE-MAKING  —  DRY.  375 

The  Obernetter  method  is  also  added  here,  as  it  first  appeared.  Scarcely 
any  one  is  ever  content  to  work  a  process  in  its  entirety.  All  have  useful 
practical  hints  from  which  the  intelligent  worker  can  draw  to  suit  his 
inclination. 

Filtering. — Strictly  speaking,  filtering  is  unnecessary,  the  passage  through  wet  flannel 
being  sufficient  to  prevent  impurities  and  air  bubbles. 

Gelatine. — Nearly  every  kind  of  gelatine  may  be  employed.  In  summer  and  in  hot 
climates  the  harder  variety  is  to  be  preferred,  in  winter  the  softer  kinds.  Emulsion  with 
soft  gelatines  always  gives  finer  negatives  than  do  hard  gelatines.  A  test  of  the  applica- 
bility of  the  gelatine  may  be  made  as  follows : 

The  silver  gelatine  made  according  to  my  formula  ought  to  be  so  far  set  in  four  hours 
at  a  temperature  of  12°  R.,  in  a  quantity  of  one  litre,  that  on  movement  of  the  vessel 
containing  it  the  mass  should  not  run,  nor  should  it  be  colored  brown  even  after  twenty- 
four  hours.  There  are  three  firms  in  Germany  whose  gelatine  I  recommend — Ch. 
Heinrich's,  in  Hochst-on-the-Main  ;  F.  F.  Crenz,  in  Miehelstadt,  in  Hesse ;  and  Simeon's 
gelatine. 

For  our  climate,  winter  as  well  as  summer,  Heinrich's,  of  Hochst-on-the-Main, 
furnishes,  under  the  name  emulsion-gelatine,  an  article  which  gives  excellent  results. 
I  work  with  this  gelatine  only.  In  summer,  when  it  is  excessively  hot,  I  add  a  portion 
of  Simeon's  hard  gelatine,  which  variety  I  also  recommend  for  warm  climates  or  hot 
weather. 

Durability  of  the  Emulsion. — If  the  emulsion,  after  washing,  is  immersed  in  alcohol  so 
that  it  is  completely  covered,  from  day  to  day  more  and  more  water  is  extracted  from  it, 
so  that  finally  it  presents  a  leathery  consistency,  in  which  condition  it  remains  for  un- 
limited time.  I  have  emulsions  which  are  three  years  old,  which  work  as  effectively  as 
on  the  first  day.  It  is  otherwise  with  emulsions  in  a  thin  state  mixed  with  albumen. 
In  winter  it  may  be  kept  for  a  month  or  so,  and  may  even  be  warmed  so  as  to  flow  upon 
the  plates;  but  in  summer  it  is  often  spoiled  in  a  few  days,  sometimes  it  may  be  kept  for 
three  weeks.  All  additions  of  antiseptics  are  unnecessary. 

Nitrate  of  Silver. — This  salt,  so  much  used  in  photography,  should  contain  no  free 
nitric  acid  in  the  preparation  of  the  emulsion.  It  should  be  dissolved  in  distilled  water, 
and  the  solution  should  not  redden  litmus  paper.  The  fused  salt  (lunar  caustic)  may 
be  used. 

Temperature  plays  an  important  part  in  the  preparation  of  the  emulsion,  and  in  the 
development  of  plates.  For  the  setting  of  the  mass  a  temperature  of  from  8°-12°  R.  is 
the  most  suitable;  on  the  contrary,  for  the  maceration  of  the  same,  the  temperature 
ought  not  to  be  under  12°  R.  Nor  should  all  preparations  for  development,  fixing,  etc., 
be  under  15°  R. 

Water. — All  kinds  of  water  suitable  for  drinking  may  be  employed  for  emulsifying,  as 
well  for  the  preparation  as  for  the  washing.  Only  for  the  solution  of  the  silver  nitrate  is 
distilled  water  demanded. 

Washing. — For  the  purpose  of  washing,  I  make  use  of  an  apparatus  of  strong,  sheet 
zinc,  of  suitable  dimensions  for  two  kilogrammes  of  emulsion.  (Fig.  328.)  a.  Interior 


376 


WILSON S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


FIG.  328. 


A  multiplicity  of  methods  is  given  here  in  order  that  the  manipulator  may 
have  a  fair  understanding  of  all  the  means  at  his  disposal. 

If  he  is  wise  he  will  choose  from  the  assortment  whatever  gives  him  the 

space  of  wash  apparatus ;  b,  the  cover ;  c,  handle  of  cover ;  d,  gum  tube  for  ingress  of 
water ;  e,  stationary  brass  tube ;  /,  gum  tube ;  g,  bent  tube  of  glass ;  h,  beaker  glass  con- 
taining the  emulsion ;  i,  tube  for  exit  of  water. 
Method  of  Using  the  Gelatine  Emulsion. — If  it 
be  desired  to  employ  the  emulsion  immediately 
after  preparation  it  should  have  the  proper  de- 
gree of  consistency  for  pouring  upon  the  plates. 
In  the  cooler  months,  from  October  to  May,  the 
emulsion  maintains  for  a  long  time  the  thinness 
necessary  for  this  purpose.  In  the  warm  months, 
from  May  to  September,  its  durability  is  doubt- 
ful, decomposition  frequently  taking  place  in  a 
week.  If  it  is  desired  to  keep  in  stock  the  emul- 
sion, during  the  summer  season,  or  for  the 
purpose  of  transportation,  the  emulsion  should 
immediately  after  washing  be  transferred  to 
strong  alcohol,  in  which  state  it  may  be  kept  for 
a  year  in  a  leathery  state  by  extraction  of  the 
water. 

To  make  use  of  this  emulsion   again,  it  is 
cut  in  small  pieces,   put  in   a  glass  bulb  or 

beaker  glass,  sufficient  water  poured  on  it,  and  left  stand  for  two  to  five  hours ;  the  water 
is  then  poured  off  and  the  vessel  transferred  to  another  containing  hot  water,  40°  to  50°  R., 
till  the  emulsion  is  completely  melted.  If  it  is  still  too  thick,  it  is  thinned  to  the  right 
consistency  with  distilled  water.  To  every  100  grammes  of  this  emulsion  2  to  5  grammes 
of  pure  albumen  are  added  (beaten  up  to  a  froth  and  suffered  to  settle) ;  the  mixture  is 
well  shaken  and  filtered  through  damp  flannel.  The  emulsion  is  then  ready  for  pouring. 
The  emulsion  should  be  put  either  in  a  beaker  glass  or  a  vessel  with  a  wide  neck,  and 
placed  in  a  vessel  of  warm  water,  30°  to  40°  R.,  before  pouring  it  upon  the  plate ;  all 
bubbles  upon  the  surface  should  be  broken.  All  this,  of  course,  is  to  be  done  in  the 
dark-room. 

The  plate  is  to  be  brushed  over  either  with  a  blender,  or  soft  brush,  dipped  in  a  solu- 
tion of  soluble  glass  (1  gramme  of  soluble  glass  to  200  or  300  grammes  of  water),  then 
dried  with  filtering  paper,  polished,  and  dusted. 

The  flowing  of  the  plate  is  done  in  the  same  manner  as  a  collodion  plate,  the  emulsion 
spreading  as  readily;  if  the  room  is  cold  it  may,  however,  be  necessary  to  slightly  warm 
the  plate  before  flowing.  The  emulsion  is  flowed  to  one  corner,  and  the  excess  poured  in 
the  bottle.  When  the  emulsion  becomes  too  thick  it  is  returned  to  the  vessel  of  hot  water. 
The  emulsion  may  be  poured  to  the  last  drop  without  affecting  the  purity  of  the  plate. 
It  is  to  be  observed  that  the  emulsion  should  not  be  poured  too  thin  upon  the  plate, 


NEGATIVE-MAKING — DRY.  377 

best  results,  and  then  adhere  to  the  same,  only  modifying  as  emergencies  may 
arise.  And  I  confess  that  emergencies  never  cease — they  are  always  arising. 

otherwise  the  resulting  negative  will  be  weak.  The  thickness  of  the  film  should  be 
about  that  of  a  strongly  iodized  collodion  plate. 

The  plate  when  coated  should  be  laid  upon  a  perfectly  level  plate  of  glass  (cold),  stone, 
or  metal,  not  above  12°  R.  After  two  to  five  minutes  the  emulsion  will  have  set,  and 
the  plate  may  be  put  in  a  perpendicular  position,  protected  perfectly  from  dust  and 
light ;  but  the  plates  should  not  be  too  closely  packed  in  the  drying  case,  they  are  best 
if  left  to  dry  spontaneously.  'The  next  day  after  preparation  the  plates  are  ready  for 
use.  They  keep  a  long  time  after  exposure. 

The  development  may  be  effected  with  any  of  the  known  developers.  I  prefer  Dr. 
Eder's  oxalate  of  iron. 

The  following  preparation  should  be  kept  on  hand  : 

A  saturated  solution  of  neutral  oxalate  of  potassa  in  water.  One  part  of  neutral 
oxalate  dissolved  in  three  parts  of  water. 

Solution  of  protosulphate  of  iron.  One  part  of  sulphate  dissolved  in  three  parts  of 
water,  and  to  every  litre  of  this  solution  five  drops  of  sulphuric  acid. 

Bromide  of  potassium  solution.     One  part  of  bromide  in  ten  parts  of  water. 

To  develop  a  place,  three  volumes  of  the  oxalate  solution  are  put  in  one  vessel  and  in 
another  glass  one  volume  of  the  iron  solution.  About  a  third  of  the  iron  solution  is  then 
poured  into  the  oxalate  solution,  and  the  mixture  flowed  over  the  plate  which  is  put  in 
a  shallow  dish  or  tray.  If  the  image  comes  up  too  quickly,  it  is  a  sign  that  the  exposure 
has  been  too  long;  but  it  may  be  saved  by  adding  more  water  to  weaken  the  solution, 
and  by  the  addition  of  a  few  drops  of  bromide  of  potassium.  If  the  image  is  too  harsh, 
the  iron  solution  is  added  till  it  is  all  used  up. 

The  negative  may  be  judged  by  the  transparency  in  from  three  to  four  minutes  after 
the  operation  is  finished.  The  plate  is  then  taken  out  of  the  solution,  washed  under  the 
hydrant,  and  trapsferred  to  the  fixing-bath  of  hyposulphite  of  soda.  After  the  fixing 
the  plate  is  washed  in  water.  The  time  of  washing  is  not  longer  than  that  demanded 
by  a  wet  plate— about  five  minutes.  If  it  is  desired  to  dry  the  plate  quickly,  it  is 
dipped  in  alcohol ;  in  ten  minutes  after  this  treat  to  spirits  it  is  dry.  Heat  cannot  be 
used. 

If  the  negative  has  not  sufficient  intensity,  which  may  be  caused  by  too  long  exposure 
or  by  too  thin  coating  of  the  plate,  I  recommend  the  following  intensifier.  After  the 
fixing  and  complete  washing  from  the  soda,  the  plate  is  flowed  over  with  the  following : 

Bromide  of  potassium,  20  grammes;  bichloride  of  mercury,  20  grammes;  water,  500 
grammes;  alcohol,  50  grammes. 

Dissolved  hot,  and  after  cooling  filtered.  The  time  (one  to  five  minutes)  is  regulated 
by  the  degree  of  intensity  desired.  It  is  then  washed  with  water  and  flowed  over  with  a 
solution  as  follows :  20  grammes  of  cyanide  of  potassium  in  500  grammes  of  water,  and 
25  grammes  of  nitrate  of  silver  in  500  grammes  of  water.  These  solutions  are  shaken 
together  until  a  permanent  precipitate  is  formed  ;  the  mixture  is  then  filtered,  and  poured 
over  the  plate  until  no  white  spot  is  visible  on  the  back  side  of  the  plate  (one  minute). 


378        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

But  they  do  not  always  require  a  modification  of  the  chemicals.     The  whole 
secret  is  ofteuer  in  the  thoughtful  manipulation  than  in  the  means. 

If  the  intensifying  has  been  carried  too  far,  all  that  is  necessary  is  to  transfer  the 
plate  to  the  hypo  bath,  where  it  is  weakened.  It  is  not  necessary  to  add  that  it  must  be 
re- washed  after  removal  from  the  fixing  bath. 

These  operations  are  performed  upon  my  plates  quicker  and  more  effectively  than  with 
other  plates,  owing  to  the  thinness  of  the  film,  its  adherence  to  the  glass,  and  the  ease 
with  which  the  chemicals  penetrate.  * 

Aids  to  the  Perfect  Working  of  the  Obernetter  Emulsion  Process. — It  is  not  a  strange 
occurrence  in  the  history  of  a  new  process  like  the  present  to  meet  with  such  contra- 
dictory results  in  its  practical  working.  On  the  one  hand,  brilliant  success  and  perfect 
satisfaction ;  on  the  other,  total  failure  and  dissatisfaction.  My  endeavor  was,  naturally  ? 
first  of  all  to  prevent  these  failures,  and  only  recently  have  I  succeeded  in  discovering 
the  principal  causes  producing  them. 

Their  prevention  was  no  easy  task;  but  now,  since  I  have  struck  at  the  root  of  the  evil, 
it  is  possible  to  furnish  a  remedy,  simple  and  efficacious.  The  principal  cause  of  failure 
lies  in  the  quality  of  the  wash-water.  Water  containing  a  high  percentage  of  carbonic 
acid  or  carbonates — that  is,  hard  water — gave  satisfactory  results ;  but  where  soft  water 
was  employed  the  failures  were  soon  manifest. 

According  to  my  opinion,  soft  water  does  not  sufficiently  penetrate  the  emulsion  strips, 
especially  if  the  strips  are  of  any  thickness,  where  the  inner  portions  are  poor  in  silver 
"but  rich  in  the  other  salts.  Those  salts  not  sufficiently  washed  out  remain  in  the  emul- 
sion, and  are  the  cause  of  the  lack  of  sensitiveness  and  flatness. 

The  case  is  different  when  hard  water  is  used.  The  chalk  combines  with  the  acids  of 
the  mass  forming  an  insoluble  compound,  liberating  free  carbonic  acid,  which  renders 
the  mass  porous,  and  facilitates  the  expulsion  of  the  soluble  salts. 

The  means  are  simple  and  the  end  easily  attained,  if  the  mass  be  cut  up  into  the 
thinnest  possible  shreds.  The  silvered  gelatine  mass  should  not  be  thicker  than  a  half 
centimetre,  the  strips  about  three  or  five  millimetres  in  thickness.  This  labor  is  not 
great,  since  the  gelatine  when  properly  set  easily  divides,  and  besides  the  whole  opera- 
tion may  be  done  in  broad  daylight.  This  seeming  trifle  is  of  such  importance  that  I 
am  convinced  that  most  of  the  failures  may  be  attributed  to  the  neglect  of  the  quality  of 
the  water  employed. 

I  have  found  that  the  following  particulars  have  not  been  sufficiently  regarded,  I 
therefore  recommend  them  again  to  a  serious  consideration  : 

The  silver  solution  must  be  poured  into  the  hot  gelatine  solution  not  below  30°  R., 
nor  over  50°  R. :  only  at  this  temperature  is  the  fluid  milky.  When  it  is  milky  it  is 
readily  cooled  and  easily  filtered. 

The  bromide  fluid  operates  directly  after  the  mixture  as  a  refrigerating  mixture,  and 
indicates  a  temperature  of  0°.  When  so  employed  it  gives  monotonous,  unsensitive 
plates.  The  temperature  ought  not  to  be  under  12°  R. ;  it  is  better  at  15°  or  18°  R. 

The  flannel  for  filtering  the  emulsion  can  only  be  used  once — a  piece  ten  centimetres 
square.  If  the  flannel  is  used  the  second  time,  black  specks  will  appear. 


NEGATIVE-MAKING  —  DRY.  379 

166.  With  all  that  has  been  provided,  still  the  great  desire  of  the  manufact- 
urers has  been  to  produce,  and  the  operators  to  have,  a  grade  of  plate  in  the 
highest  degree  sensitive,  with  which  results  equal  to  slower  ones  could  be  had. 
Up  to  the  present  this  wish  has  not  been  satisfied. 

An  advantage  gained  in  this  direction  has  been  ever  opposed  by  some  per- 

The  emulsion  must  be  kept  under  alcohol  before  it  is  melted.  It  must  be  freed  from  the 
alcohol,  which  is  best  effected  by  washing  in  the  apparatus  for  three  hours.  After  the 
melting  it  must  be  thinned  with  water  till  it  flows  easily  on  pouring. 

The  drying  of  the  plate  must  be  completed  in,  at  least,  twenty-four  hours,  and  must 
be  done  in  an  airy  and  perfectly  dark  room. — J.  B.  OBERNETTER. 

166.  Development  of  Instantaneous  Negatives  with  Carbonate  of  Soda.^To  develop  an 
instantaneous  negative  13  x  18  centimetres  (5y  x  7j-  in.),  I  place  in  a  glass  60  grammes  (2 
oz.)  of  water,  and  add  immediately,  and  without  taking  the  trouble  to  measure,  from  5 
to  10  c.c.  (1J  to  3  drachms)  of  a  20  per  cent,  solution  of  sulphate  of  soda;  I  also  add  to 
this  about  20  c.  c.  (6  drachms)  of  a  solution  in  water  of  crystals  of  ordinary  carbonate 
of  soda  (but  free  from  sulphate  of  soda),  this  solution  should  be  at  least  20  per  cent., 
even  30  per  cent,  would  not  be  injurious.  The  alkaline  mixture  thus  made  in  the  glass 
I  throw  over  the  plate,  allowing  it  to  remain  two  minutes  in  order  that  the  gelatine  film 
should  become  completely  saturated.  After  two  or  three  minutes  I  place  at  the  bottom 
of  my  glass,  which  is  now  empty,  10  centigrammes  (3  drachms)  at  least  of  a  solution  of 
pyrogallic  acid  in  alcohol:  Alcohol  at  40°,  23  grains;  pyrogallic  acid,  3  drachms. 

To  mix  immediately  I  pour  into  my  glass,  over  the  acid  that  is  there,  the  alkaline 
solution  which  is  in  the  dish,  and  I  cast  anew  the  whole  over  the  negative.  In  a  very 
short  time,  even  with  the  shortest  exposures,  the  high  lights  appear,  and  after  which  the 
details;  by  agitating  continually  the  dish,  the  negative  covers  itself  by  degrees  in  all  its 
parts.  Be  careful  especially  not  to  look  at  it  too  soon  by  withdrawing  it  from  the  bath 
which  is  in  its  first  action.  In  this  state  the  reducing  action  goes  on  with  much  more 
energy  than  if  you  were  to  stop  this  action  by  withdrawing  your  negative  from  the  bath 
to  look  at  it  by  transparency,  to  again  take  it  up  by  replunging  the  negative  into  a  dish. 
A  time  will  come  when  you  will  see  that  the  action  is  stationary,  then  look  by  trans- 
parency; if  the  whites  are  wanting  in  detail,  add  to  the  bottom  of  the  glass  some  carbo- 
nate without  bromide,  mix  by  pouring  on  this  carbonate  the  liquid  which  is  in  the  dish, 
and  throw  the  whole  over  the  negative.  The  details  are  made  to  appear  by  the  successive 
additions  of  the  carbonate.  When  all  the  details  have  appeared,  it  is  always  necessary 
to  intensify  your  negative,  which,  in  coming  from  the  hyposulphite,  would  be  too  weak. 
For  this  you  put  in  your  glass  from  5  to  10  c.  c.  (1 J  to  3  drachms)  of  pyrogallic  acid, 
mix  with  the  liquid  of  the  dish  and  throw  over  the  negative.  In  an  interval  of  about 
two  minutes  you  again  put  in  the  glass  from  5  to  10  c.  c.  (1£  to  3  drachms)  of  the  carbo- 
nate solution ;  you  again  mix  with  the  remainder  of  the  bath  and  throw  over  the  nega- 
tive. By  these  two  successive  additions  the  negative  is  progressively  intensified;  with 
a  little  patience,  if  the  intensity  does  not  appear  to  be  sufficient,  you  can  increase  it  by 
alternating  the  solutions  of  pyrogallic  acid  and  carbonate  of  soda.  I  generally  finish 


380         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

verse  drawback.  Some  manufacturers  have  become  so  exasperated  as  to  assert 
that  quick  plates  are  "sour  grapes"  after  all,  and  for  some  purposes  "long 
exposures"  are  deemed  best.  Mons.  Balagny,  a  persistent  Parisian  photog- 
rapher, has  taken  issue  with  this  opinion,  and  after  much  patient  experiment, 
offers  a  means  of  development  which,  he  claims,  will  produce  from  the  most  sen- 
sitive plates,  the  best  results  with  the  greatest  ease.  I  add  his  method  as  sent 

with  the  carbonate.  Now  wash  in  two  waters,  pass  into  the  alum  bath,  and  fix.  Do  not 
fear  to  make  use  of  the  sulphite,  as  it  is  this  substance  that  gives  the  beautiful  tones  of 
the  negative;  if  you  have  the  least  coloration,  it  is  because  there  was  not  enough  sul- 
phite. You  must  use  enough,  but  not  too  much,  as  it  is  said  that  it  retards  the  develop- 
ment. 

In  the  above  formula}  the  persons  who  are  accustomed  to  using  carbonate  of  potash 
can  use  carbonate  of  soda  instead.  With  preparations  of  gelatino-bromide  of  great 
rapidity,  it  is  possible,  with  the  above  development,  to  give  to  an  instantaneous  negative 
the  same  brilliancy  and  the  same  intensity  as  one  that  is  not  instantaneous. 

In  experimenting,  I  was  led  to  plunge  the  flexible  plates  in  developing  baths  of  great 
energy.  It  is  especially  well  in  photography  to  know  how  to  dare.  I  sought  for  an  acci- 
dent, and  I  found  an  excellent  developer.  As  it  is  the  carbonates  that  most  frequently 
produce  blisters,  I  plunged  the  flexible  plates  in  pure  carbonate  at  twenty-five  per  cent., 
or  at  saturation,  before  the  development.  The  plates  used  had  been  exposed  one  or  two 
seconds,  at  the  furthest.  As  soon  as  I  afterward  added  pyrogallic  acid,  even  in  very 
small  quantity,  the  image  appeared  with  such  rapidity  and  such  intensity  that  I  under- 
stood that  I  had  before  me  a  process  which  would  give  me  instantaneousness  without 
the  least  trouble. 

I  make  a  solution  of  carbonate  of  soda  at  25  per  cent. ;  I  also  make  a  solution  of  sul- 
phite of  soda  at  25  per  cent.,  say  250  grammes  (8  ounces  Troy)  of  one  or  the  other  of 
these  two  salts,  for  a  quart  of  water.  I  allow  it  to  settle,  and  decant  for  use.  To  develop, 
place  in  a  glass  from  25  to  30  c.  c.  (7  fluidrachms  to  1  fluidounce)  of  carbonate  of  soda, 
and  from  15  to  20  c.  c.  (4  fluidrachms  to  5j  fluidrachms)  of  sulphite  of  soda,  the  two 
solutions  being  mixed  together.  The  flexible  plate  is  placed  in  a  moulded  glass  dish,  so 
as  to  be  able  to  follow  the  development  by  transparency.  (I  use  moulded  glass  because 
the  developer  is  so  strong  that  it  entirely  dissolves  the  marine  glue  with  which  are  made 
the  wood-and-glass  receptables  for  the  bath.)  The  liquid  is  thrown  on  the  pellicle, 
which  is  well  wet,  and  allowed  to  remain  in  this  state  for  about  two  minutest 

During  this  time  of  waiting,  place  in  the  glass,  which  is  now  empty,  from  10  to  15  c.  c. 
(4  fluidrachms)  of  pyrogallic  acid  dissolved  in  alcohol  in  the  proportion  of  10  grammes 
(3  drachms)  to  150  c.  c.  (5  fluidounces)  of  alcohol.  A  large  pinch  of  pyrogallic  acid  in 
powder  may  also  be  put  at  the  bottom  of  the  glass.  Whether  the  acid  is  used  in  powder 
or  in  an  alcoholic  solution,  the  mode  of  operating  is  the  same,  and  the  result  will  be 
identical.  All  the  alkaline  liquid  which  is  in  the  dish  is  poured  on  the  acid  and  the 
most  intimate  mixture  is  obtained.  The  whole  is  again  poured  on  the  flexible  plate 
which  has  remained  adhering  to  the  bottom  of  the  dish.  After  agitation,  and  in  a  very 


NEGATIJVE-MAKING  —  DRY.  381 

from  France,  separated  from  the  notes  on  developers,  that  it  may  be  more 
fairly  understood.     The  two  papers  were  presented  about  three  months  apart. 

167.  The  annoyances  which  beset  the  dry-plate  maker  and  worker  are 
numerous.  Gelatine  is  a  far  less  manageable  substance  than  collodion — as  sen- 
short  time,  the  image  appears,  but  at  first  with  a  rather  grayish  tint;  then  it  is  the  blacks 
alone  that  come  up  without  intermission,  until  it  is  deemed  that  the  action  is  insufficient. 
During  all  the  time  of  development  the  whites  are  very  well  preserved ;  I  may  say  that 
I  did  not  miss  one,  and  always  without  bromide.  But  a  little  bromide  may  be  added 
with  advantage  when  the  slow  stop  has  been  used.  In  this  case  add,  at  the  start,  to  the 
mixture  of  carbonate  and  sulphite,  from  5  to  10  drops  of  a  solution  of  bromide  of  ammo- 
nium in  water  in  the  proportion  of  10  per  cent. 

When  the  development  is  ended  wash  well,  especially  if  pyrogallic  acid  dissolved  in 
alcohol  has  been  used.  When  the  greasy  streaks  have  entirely  disappeared,  give  an 
alum  bath — 60  grammes  (2  fluidounces")  for  1000  grammes  (34  fluidounces)  of  water — and 
after  remaining  two  minutes  in  this  bath,  fix  with  hyposulphite.  The  rest  of  the  opera- 
tion for  drying  the  flexible  plates  has  been  already  described. — M.  BALAGNY. 

167.  I  have  often  found  it  necessary  to  intensify  parts  of  negatives.  This  has  been 
done  with  an  intensifier  known  as  Edwards'.  It  is  made  by  mixing  a  saturated  solution 
of  bichloride  of  mercury  with  a  saturated  solution  of  iodide  of  potassium,  till  there  is  a 
slight  red  precipitate,  which  is  dissolved  by  adding  a  small  crystal  of  hyposulphite  of 
soda.  It  can  be  applied  with  a  brush  to  any  part  which  it  is  wanted  to  intensify. 
This  will  be  found  a  very  valuable  dodge. 

Another  dodge  is  just  reversing  the  above,  and  is  used  for  local  reduction  or  for  reducing 
the  intensity  of  the  whole  negative  where  it  is  too  intense.  The  negative  is  flowed  with 
a  strong  solution  of  red  prussiate  of  potash,  washed,  and  put  into  the  hypo  bath,  and 
this  can  be  repeated  till  the  negative  is  thin  enough,  or  parts  can  be  reduced  by  applying 
the  prussiate  of  potash  solution  with  a  brush  to  those  parts  only,  followed  by  the  hypo. 

Dodge  third :  I  have  been  troubled  during  the  hot  weather  with  the  rapid  discolora- 
tion of  the  developing  solutions  and  consequent  coloring  of  the  negatives,  which  has  not 
been  taken  out  by  the  alum  bath,  but  in  all  cases  the  most  obstinate  stain  has  given  way 
to  an  application  of  Mr.  Carbutt's  clearing  solution  (1£  ounce  of  powdered  alum,  20 
ounces  of  water,  and  \  ounce  of  sulphuric  acid). — GEO.  HANMER  CROTJGHTON. 

I  give  my  two  methods: 

Iron  Intensifier. — The  following  stock  solution,  which  keeps  very  well,  is  prepared: 
G.  5  parts  of  good  white  gelatine,  dissolved  in  50  parts  of  glacial  acetic  acid,  diluted 
with  100  parts  of  water,  and  filtered. 

For  use,  dissolve — E.  4  parts  of  sulphate  of  iron  in  120  parts  of  water;  filter,  and  add 
10  parts  of  solution  G.  This  solution  keeps  for  some  time. 

S.  3  parts  of  nitrate  of  silver  in  100  parts  of  water,  to  which  are  added  4  parts  of  glacial 
acetic  acid.  Also  keeps  well. 

After  the  plate  has  been  washed  thoroughly,  it  is  placed  for  some  minutes  in  a  satu- 
rated solution  of  alum ;  in  order  to  prevent  the  risk  of  frilling  the  film,  in  the  following 
acid  bath :  After  the  alum,  the  plate  is  rinsed,  and  placed  for  about  five  minutes  in  a 


382         WILSON'S  QUARTER  CENTURY-  IN  PHOTOGRAPHY. 

sitive  as  a  neuralgic  person  to  every  atmospheric  change — most  exacting  in  the 
treatment  it  requires  at  the  hands  of  the  manipulator. 

three  per  cent,  glacial  acetic  acid  bath.  In  the  meantime,  pour  (for  a  5  x  8  plate)  about 
5  c.  cm.  of  silver  solution  (S)  into  a  glass,  and  place  that  and  the  bottle  with  the  solu- 
tion E  within  easy  reach.  The  plate  is  then  removed  from  the  acid  bath,  rinsed,  and 
the  solution  E  at  once  poured  over  it,  taking  care  that  the  plate  is  well  covered ;  if  neces- 
sary, aid  with  the  finger.  Care  must  be  taken  to  have  an  abundance  of  solution  on  the 
plate.  The  solution  is  now  poured  off  the  plate  into  the  glass  containing  the  solution  S> 
and  then  at  once  pour  back  again  over  the  plate.  The  intensification  goes  on  evenly. 
If  red  patches  form,  it  becomes  necessary  to  rinse  forthwith,  and  then  to  pour  on  a  two 
per  cent,  solution  of  cyanide  of  potassium.  But,  if  care  is  taken,  nothing  of  the  sort 
will  appear. 

Sublimate  Intensifier. — I  strengthen  first  somewhat  with  the  iron-silver  intensifier, 
although  I  can  use  it  also  without  the  latter.  Here  is  the  formula:  4  per  cent,  solution 
of  sublimate  and  a  2  per  cent,  solution  of  cyanide  of  potassium.  Both  keep  a  good 
while. 

The  manipulation  is  quite  simple — after  the  sublimate  has  acted  thoroughly,  and  the 
plate  has  been  rinsed  well,  the  cyanide  solution  is  poured  over  it.  A  warm  brown  tone 
appears  at  once,  and  the  shades  remain  quite  clear;  when  ammonia  is  used,  this  is  sel- 
dom the  case.  Also,  no  danger  of  turning  yellow  is  to  be  feared.  Of  course,  thorough 
washing  is  strictly  necessary. — M.  WIGHT. 

It  is  useless  to  attempt  the  intensification  of  a  fogged  negative.  An  overexposed  and 
fogged  plate  may  be  considered  past  doing  anything  with,  and,  on  the  other  hand,  little 
or  nothing  can  be  done  with  an  underexposed  or  underdeveloped  plate,  where  no  detail 
has  been  brought  out.  But  it  sometimes  happens  that  a  plate  comes  out  of  the  fixing 
bath  clear  in  the  shadows  and  full  of  the  proper  details  throughout  the  rest,  but  wanting 
in  sufficient  intensity  to  make  a  good  print.  These  are  the  cases  in  which  intensifica- 
tion comes  so  well  into  play. 

The  process  is  extremely  simple,  but  at  the  same  time  one  requiring  a  certain  amount 
of  care  and  cleanliness,  for  the  principal  agent  used  is  the  bichloride  of  mercury,  a  potent 
chemical,  tending  to  inequality  in  its  action,  unstable,  and  highly  poisonous.  Of  the 
different  formula  given,  I  have  found  that  of  mercury,  in  conjunction  with  cyanide  of 
silver  (which  will  be  found  in  the  directions  accompanying  Carbutt's  plates),  the  most 
reliable  and  satisfactory — not  only  for  dry  but  also  for  wet  plates,  and  although  a  nega- 
tive may  be  very  satisfactorily  intensified  after  it  has  been  dried,  I  think  the  most  per- 
fect and  certain  results  are  to  be  obtained  immediately  after  the  final  washing  (the  plate 
having,  of  course,  been  submitted  to  the  alum  bath)  and  before  drying,  and  in  the  case 
of  negatives  that  have  already  been  dried,  they  should  be  thoroughly  moistened  again 
in  clean  water  before  treating,  and  in  both  cases  the  superfluous  water  should  be  drained 
and  carefully  blotted  from  the  surface.  When  this  has  been  done,  pour  a  sufficient 
quantity  of  the  mercury  solution  into  one  of  your  glass  or  porcelain  developing  pans  to 
cover  the  bottom  to  the  depth  of  a  quarter  of  an  inch  or  so,  set  the  negative  perpendicu- 
larly into  this  and  lower  it  on  the  solution,  face  down,  with  an  even  motion  and  without 


NEGATIVE-MAKING  —  DRY.  383 

The  morbid  desire  for  "  lightning  "  plates  often  results  in  weak  negatives,  so 
.that  the  demand  for  a  safe  and  effective  means  of  intensification  has  had  a  great 
deal  of  careful  consideration.  The  best  way  is  to  use  such  plates  as  will  give 
the  proper  density  without  after  treatment,  but  since  this  cannot  always  be,  we 
must  turn  to  the  intensifier. 

pausing ;  in  this  way  the  solution  will  flow  equally  across,  air  bubbles  will  be  forced  out, 
and  streaks  and  lines  will  be  avoided.  A  scrap  of  glass  or  rod  should  be  used  to  keep 
the  face  of  the  plate  from  touching  the  bottom  of  the  dish,  and  it  will,  by  serving  to 
raise  the  plate  out  of  the  solution,  save  the  fingers,  the  mercury  being  very  destructive 
to  the  skin.  When  the  image  has  become  equally  and  thoroughly  whitened,  the  plate 
should  be  removed  and  well  washed  and  drained.  The  next  solution,  the  cyanide,  is 
best  applied  by  having  an  abundance  in  a  pan,  so  as  to  be  sure  of  thoroughly  covering 
the  plate,  and  dropping  the  latter  in,  face  up,  as  in  developing,  and  keeping  the  pan  in 
motion  so  that  the  solution  will  flow  back  and  forth  from  end  to  end.  In  a  few  moments 
the  whitened  image  of  the  negative  will  be  turned  to  a  clear  deep  brown,  and  when  the 
change  has  taken  place  equally  and  completely,  the  plate  may  be  removed  and  well 
washed  and  dried.  The  whole  process  may,  of  course,  be  conducted  in  open  daylight. 
Always  return  the  solutions  immediately  to  their  respective  bottles,  and  wash  thoroughly 
the  pans ;  cleanliness  is  essential  to  the  success  of  the  process,  and  also  important  on 
account  of  the  poisonous  nature  of  the  solutions  used. 

Negatives  that  have  been  successfully  intensified  and  which  it  is  desired  to  preserve 
for  any  considerable  length  of  time,  should  be  varnished.  Intensified  wet  plates  are 
particularly  liable  to  change,  returning  unequally  to  the  bleached  condition,  and  my 
experience  has  been  that  varnishing  effectually  prevents  any  change ;  and  although  I 
have  not  as  yet  noticed  instability  with  the  dry  plates,  yet  from  the  nature  of  the  chem- 
icals used,  good  negatives  (intensified),  which  I  wish  to  preserve,  I  varnish  as  a  matter 
of  thorough  precaution. — XANTHUS  SMITH. 

Gelatine  plates  have  many  virtues,  but  associated  with  these  virtues  are  a  few  failings, 
one  of  which  is  that  they  will  sometimes,  in  spite  of  all  the  care  spent  upon  them  in 
developing,  yield  thin  and  ghostly  images.  This  tendency  is  greater  in  proportion  to 
the  rapidity  of  the  sensitive  surface,  as  it  is  difficult  to  intensify  the  weak  productions 
without  clogging  the  shadows  and  destroying  the  half  tones. 

I  have  had  very  little  success  with  the  use  of  mercury  as  an  intensifier,  and  the  use  of 
the  pyrogallate  of  silver  and  the  ferricyanide  of  potassium  and  uranium  are  out  of  the 
question.  I  prefer  the  use  of  the  old  method  of  intensifying  with  dilute  hydrosulphate 
of  ammonia  or  solution  of  sulphide  of  potassium.  These  are  not  the  most  delectable 
compounds  in  the  world,  nevertheless  the  photographer  should  not  abandon  them  on 
that  account. 

By  the  use  of  either  of  these  chemicals  there  will  be  no  danger  of  destroying  the  nice 
gradations  of  tone  on  the  negative,  a  danger  frequently  encountered  with  the  use  of  the 
well-known  intensifiers. 

The  solution  must  not  be  too  strong,  and  it  does  not  make  any  difference  whether  the 
plate  has  been  developed  by  pyro  or  oxalate.  Neither  is  there  any  necessity  of  so  thor- 


384         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

168.  Again,  from  lack  of  knowledge  as  to  the  exposure,  or  from  careless 
haste,  the  negative  is  too  strongly  developed,  and  as  a  result,  is  harsh  and  hard , 
and  too  dense. 

ough  a  washing  of  the  plate  as  is  demanded  when  we  make  use  of  mercury  for  intensi- 
fying.— L.  REGNATJLT. 

168.  To  Reduce  a  Negative. — Dr.  Eder  has  recently  published  some  valuable  notices  con- 
cerning the  reduction  of  too  strongly  developed  plates  with  chloride  of  iron  and  oxalate 
of  potassa.  Dr.  Eder  employs  the  mixture  as  follows :  A.  1  part  chloride  of  iron,  dis- 
solved in  8  parts  water.  B.  2  parts  neutral  oxalate  of  potassa  in  8  parts  water. 

Both  solutions  keep  a  long  time  without  deteriorating.  Immediately  before  using 
equal  parts  of  A  and  B  are  mixed,  forming  a  bright  green  solution,  which  keeps  well  for 
several  days  iu  the  dark,  but  decomposes  in  one  day  in  the  light.  Of  this  mixture  a 
little  is  added  to  a  fresh  and  strong  solution  of  hypo.  In  difficult  cases  1  part  hypo  and 
i  to  J  of  iron  solution  are  employed.  The  plate  to  be  reduced  is  placed  in  this  solution. 
The  image  weakens  quickly  and  uniformly.  The  plate  is  taken  out  and  washed  just  be- 
fore the  desired  reduction  is  reached,  because  the  action  continues  during  the  washing, 
gradually  diminishing  under  the  stream  from  the  tap.  This  reducer  acts  on  plates  devel- 
oped either  with  pyro  or  oxalate,  and  does  not  destroy  the  details  in  tfye  shadows,  like 
cyanide.  There  is  also  less  tendency  to  frill  than  with  the  cyanide  bath.  The  reducing 
process  of  Mr.  Lenhad  for  weakening  certain  portions  of  the  negative  is  most  excellent. 
A  pad  of  linen  is  dipped  in  alcohol,  and  rubbed  over  the  dry  film  until  the  dark  parts 
brighten  up.  This  is  effected  without  any  loss  of  detail,  and  without  the  slightest  injury 
to  the  film.  The  finer  parts  may  be  rubbed  with  a  flexible  piece  of  wood  dipped  in 
alcohol.  I  saw,  at  the  establishment  of  the  Court  photographer,  Herr  Burger,  difficult 
retouching  effected  in  this  manner. — DK.  H.  W.  VOGEL. 

Managing  an  Overdeveloped  Plate. — After  pouring  the  developer  on  my  plate,  I  had  the 
satisfaction  of  seeing  what  would  have  been  a  very  nice  negative  come  up.  But  just  at 
this  time  I  was  urgently  called  away  and  compelled  to  remain  a  couple  of  hours.  On 
returning  to  my  dark-room,  I  found  the  plate  in  my  dish  so  intense  I  could  not  see 
through  it.  After  fixing  about  three  hours  I  set  it  aside  as  "  no  good,"  and  left  it  about 
a  week.  One  cloudy  day,  rummaging  for  a  negative  which  had  been  misplaced,  I  ran 
across  this  plate — I  cannot  say  negative.  Thinking  I  would  experiment  a  little,  I  put  it 
in  the  washing  tray  and  let  soak  a  short  while,  after  which  I  put  it  in  the  citric  acid 
bath,  which  seemed  to  have  not  the  least  effect  on  it.  Remembering  the  way  in  which 
I  had  reduced  a  number  of  negatives,  I  thought  it  would  probably  work  on  this,  but  was 
not  prepared  for  the  result  which  followed. 

I  prepared  my  chemicals  as  follows :  Make  a  saturated  solution  of  iodine  in  alcohol 
(98  per  cent.),  and  a  saturated  solution  of  cyanide  of  potassium  in  water.  I  proceeded  to 
flow  my  negative  with  pure  alcohol,  after  all  the  greasy  lines  had  disappeared  from  the 
film.  I  then  applied  the  saturated  solution  of  iodine  to  the  plate,  and  distributed  it 
evenly  but  quickly  over  the  surface  with  a  tuft  of  cotton. 

I  then  immediately  flowed  the  cyanide  (weakened  about  one-half  with  water)  off  and 
on,  until  it  dissolved  the  precipitate  formed  by  the  iodine,  which  is  of  a  whitish-green 


NEGATIVE-MAKING  —  DRY.  385 

111  such  cases  the  careful  application  of  a  reducing  agent  must  be  made.  A 
difficulty  always  occurs  to  decide  the  degree  of  reduction  allowable.  Some- 
tint  (I  believe  it  is  iodide  of  silver).  And,  presto!  changed  from  absolute  darkness; 
there  appeared  an  image  in  full  detail,  everything  is  as  clear  as  can  be,  such  as  a  sand- 
box to  the  right  of  the  principal  figure,  with  the  grain  of  the  wood,  and  every  row  of 
brick,  from  the  immediate  foreground  to  the  walls  of  a  house  in  the  distance. 

After  again  applying  the  iodine  and  cyanide,  I  washed  it  thoroughly  (the  film  must  be 
washed  under  the  tap,  and  rubbed  until  the  greasy  effect  of  the  alcohol  is  done  away 
with)  and  had  a  nice,  brilliant  printing  negative ;  of  course,  a  trifle  slower  than  if  rightly 
timed  and  developed. — DENSITY. 

Among  the  many  methods  recommended,  I  have  found  the  following  to  be  the  most 
effectual  in  abating  excessive  energy,  especially  when  the  density  is  the  result  of  over- 
exposure  : 

It  consists  of  a  mixture  of  ferricyanide  of  potassium  (red  prussiate  of  potash)  and  hy- 
posulphite of  soda ;  both  solutions  are  of  equal  strength,  and  are  used  in  equal  quantities. 
About  one  ounce  of  ferricyanide  to  sixteen  ounces  of  water,  and  the  same  strength  of 
solution  of  hyposulphite  of  soda.  The  reduction  is  gradual  and  entirely  under  control. 

Now  another  advantage  of  this  mixture  is  that  it  can  be  used  as  a  local  reducer.  All 
that  is  necessary  is  to  paint  over  with  a  brush  the  dense  portions,  and  then  immerse  the 
negative,  after  a  little  while,  in  the  hypo  wash,  and  dry.  If  the  reduction  is  not  suffi- 
cient, repeat  the  process  until  you  are  satisfied.  The  beauty  of  this  method  is  that  it 
may  be  applied  to  the  reduction  of  over-printed  paper  pictures.  Use  it  in  the  same 
way.  The  tone  of  the  paper  photograph  is  not  hurt  in  the  least,  and  the  whole  picture 
much  improved. — PRACTIQUE. 

First  diagnose  the  case  and  find  out  the  cause  of  density  before  applying  the  nostrum. 
Sometimes  I  have  found  that  the  density  is  due  to  over-exposure.  When  this  is  the  case, 
I  make  use  of  a  recipe  which  I  found  in  one  of  the  German  photographic  journals. 

I  place  the  negative  in  a  bath  of  chloride  of  copper,  to  bleach.  After  washing,  rede- 
velop with  a  concentrated  solution  of  ferrous  oxalate.  Do  not  fail  to  make  the  ferrous 
oxalate  strong;  if  you  do  not,  you  will  defeat  your  object,  and  only  make  your  negative 
stronger  and  more  dense.  Sometimes  the  negative  is  too  intense  in  the  high  lights,  but 
still  has  graduated  half  tones.  Now  I  put  such  a  negative  in  the  chloride  of  copper  until 
the  image  seen  from  the  back  appears  white.  Develop  again  slowly  with  the  oxalate, 
and  carefully  watch,  through  transmitted  light,  the  back  of  the  plate.  It  will  be  found 
that  detail  in  the  shadows  is  first  reduced  and  appears  black  on  the  back  of  the  plate, 
then  the  half  tones,  and  finally  the  high  lights  alone  still  appear  white.  The  plate  is 
now  carefully  washed  and  put  in  the  hypo  solution  until  the  white  portions  are  dissolved. 
In  this  manner  the  high  lights  alone  are  reduced,  and  the  whole  negative  made  more 
harmonious. 

Another  excellent  method  for  reduction  of  intensity  I  have  found  to  be  a  mixture  of 
ferricyanide  of  potassium  (red  prussiate  of  potash)  and  hyposulphite  of  soda.  I  think 
it  was  first  recommended  by  Farmer,  of  England. 

Both  solutions  are  of  equal  strength.  About  one  ounce  of  ferricyanide  to  sixteen 

25 


386         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

times  no  amount  of  coaxing  and  cajoling  will  "save"  a  plate,  and  it  must 
be  discarded. 

ounces  of  water,  and  the  same  strength  of  solution  for  hypo.  The  reduction  is  effected 
gradually  and  entirely  under  control.  It  has  also  the  advantage  of  being  employed  as  a 
local  reducer ;  for  this  purpose  all  that  is  necessary  is  to  pour  over  the  portion  requiring 
reduction  with  the  ferricyanide  and  then  subject  it  to  the  hypo  bath.  I  have  also  read 
in  the  Philadelphia  Photographer,  of  the  same  solution  being  used  for  reducing  over- 
printed paper  photographs  with  great  success,  without  affecting  the  tone  of  the  print  in 
the  least.  I  found  it  to  be  true. 

Although  I  recommend  this  latter  recipe,  I  still  hold  up  for  the  virtues  of  the  chloride 
of  copper  mentioned  above. 

If  chloride  of  copper  cannot  be  procured  at  the  chemist's  shop,  it  may  be  easily  made 
by  simply  mixing  common  salt  with  a  solution  of  blue  vitriol  or  sulphate  of  copper.  It 
may  also  be  used  locally  as  the  ferricyanide,  and  will  be  found  to  work  admirably.  The 
chloride  of  copper  yields  a  portion  of  its  chlorine  to  the  metallic  silver  of  the  negative, 
forming  a  thin  layer  of  chloride  of  silver,  which  is  easily  dissolved  in  the  fixing  bath. — 
H.  K.  SEYBOLD. 

My  friend  Rothe,  of  Cassel,  was  the  first  to  call  attention  to  the  circumstance  that  the 
green  crystals  sometimes  formed  in  the  ferrous  oxalate  developer,  if  dissolved  in  hypo- 
sulphite, form  an  excellent  reducing  agent  for  too  densely  developed  (not  intensified), 
negatives.  I  tried  his  formula  and  confirm  his  statements ;  nevertheless  I  persisted  in 
the  old  method  of  chloride  of  copper,  because  I  was  used  to  it,  and,  moreover,  I  may  add, 
I  had  spoiled  some  negatives  with  the  iron  salt.  But  later,  on  obtaining  more  of  the 
green  crystals  in  the  process  of  restoration  of  the  oxalate  developer,  I  did  not  throw  them 
away,  but  tried  the  experiment  again,  and  this  time  with  considerably  more  vim,  and 
now  I  am  so  satisfied  and  confident,  from  a  practical  as  well  as  a  theoretical  point  of 
view,  that  I  am  resolved  to  make  the  facts  known  for  the  good  of  the  profession.  I  there- 
fore recommend  it  to  my  professional  brethren  as  the  most  excellent,  absolutely  safe 
method  with  which  I  am  acquainted. 

Let  us  proceed  to  the  practical  method  for  obtaining  the  green  sesquioxalate  of  potassa 
(kalium  ferridoxalate)  from  the  old  developer. 

To  every  litre  of  old  developer,  sixteen  grammes  of  dried  crystallized  oxalic  acid  are 
added ;  and  the  flask  with  the  reddish-brown  precipitate,  which  is  allowed  to  remain 
with  the  necessary  precautions,  put  in  hot  water.  After  repeated  shaking,  and  when  the 
oxalic  acid  is  all  dissolved,  it  will  be  perceived  that  the  greater  part  of  the  red  deposit 
has  been  dissolved  on  longer  heating  in  the  flask,  or  on  pouring  out  into  a  porcelain  dish 
the  residue  is  finally  dissolved.  The  last  remnant  will  disappear  on  adding  a  few 
grammes  of  oxalate  of  potassa  and  heating.  It  is  now  filtered,  while  still  hot,  into  a 
clean  dish  and  exposed  in  a  cool  but  not  too  light  place ;  the  air  supplies  the  little  oxygen 
which  is  still  needed. 

After  twelve  or  twenty-four  hours,  the  greater  part  of  the  kalium  ferridoxalate  is  con- 
verted into  the  beautiful  emerald-green  crystals  spoken  of.  The  mother  liquid  is  poured 
off,  and  the  crystals  dried  on  several  thicknesses  of  blotting-paper  in  a  room  not  too 
bright. 


NEGATIVE    MAKING  —  DRY.  387 

.Let  it  be  remembered,  once  for  all,  if  anything  is  expected  from  a  defective 
emulsion  plate,  it  must  be  earned  by  patience,  care,  and  skill. 

From  one  litre  there  will  result  about  eighty  or  ninety  grammes  of  this  salt.  The  salt 
is  preserved  in  a  glass  flask  in  the  dark,  for  it  is  somewhat  sensitive  to  light ;  it  keeps 
well  if  thoroughly  dry.  If  allowed  to  remain  in  the  light,  it  throws  down  a  yellow  pre- 
cipitate of  ferridoxalate.  It  is  but  sparingly  soluble  in  water,  but  dissolves  in  a  solution 
of  hyposulphite  of  soda,  forming  a  beautiful  green  color.  It  is  this  solution  of  hyposul- 
phite which  is  to  be  used  as  the  reducing  agent  of  dense  negatives.  Ten  grammes  of  the 
salt  in  one  hundred  cubic  centimetres  of  fresh  hyposulphite  solution,  give  an  actively 
working  solution,  but  I  would  recommend  the  use  of  only  one-half  this  strength  (five  to 
one  hundred).  The  solution  can  be  applied  during  daylight,  by  pouring  it  in  a  dish; 
the  negative  as  it  comes  out  of  the  hypo  need  not  be  washed,  but  simply  laid  in  it,  and 
from  time  to  time  lifted  out,  and  the  transparency  tried  till  the  desired  result  is  obtained, 
for  the  action  is  continued  somewhat  in  the  water,  especially  if  the  solution  has  been 
strong. 

This  solution  will  keep  for  a  considerable  time,  all  that  is  necessary  is  to  filter  it  from 
the  deposit  formed ;  when  it  becomes  weak,  strengthen  it  a  little  with  the  green  salt. 
Parts  of  the  negatives  may  be  brushed  over  with  a  pencil  dipped  in  the  solution,  when 
other  portions  do  not  need  reduction  ;  but  observe  to  wash  the  negative  thoroughly. — H. 
JK.  SEYBOLD. 

I  may  here  remark  that  while  it  is  among  salts  that  photographers  look  for  their  sensi- 
tive medium,  it  is  among  reducing  agents  that  they  look  for  their  aids  to  rapidity,  devel- 
opers, and  accelerators,  and  to  the  class  of  acids  for  their  restrainers. 

The  first  step  in  the  production  of  a  modern  negative  is  the  formation  of  a  nicely 
Balanced  insoluble  salt,  and  the  suspension  thereof  in  a  vehicle  capable  of  supporting  it, 
mechanically  only.  The  next  is  irregularly  to  alter  the  tendency  of  the  sensitive  salt  to 
undergo  decomposition  or  reduction.  This  may  be  done  in  a  variety  of  ways.  The  film 
containing  the  particles  of  salt  may  be  compressed  unequally  by  physical  force ;  minute 
metallic  substances  gently  and  simply  be  laid  upon  the  surface ;  or  it  may  be  unequally 
heated;  or  it  may  be  exposed  over  the  mouth  of  a  bottle  containing  ammonia;  in  all  of 
which  cases  a  visible  trace  of  the  direction  of  the  action  of  the  force  applied  in  the  dark 
may  be  developed.  Another  method  of  obtaining  the  same  result  is  to  expose  the  sensi- 
tive salt  to  light,  when  again  a  visible  image  of  the  direction  and  strength  of  the  force 
employed  may  be  developed.  Development  being  merely  the  carefully  regulated  pro- 
duction of  metal  from  salt,  we  see  that  the  reduction  of  density  is  the  production  of  salt 
from  metal,  and  removal  in  place  of  deposition.  ..... 

Mr.  John  Spiller,  F.C.S.,  who  seems  to  have  experimented  with  most  of  the  density 
reducers  familiar  to  myself,  gives  (page  68,  Year  Book  of  Photography,  1884)  a  formula 
•which  I  have  found  to  answer  admirably.  He  summarises  its  action  thus:  "  The  chemi- 
cal action  is  practically  the  attack  of  metallic  silver  with  cupric  chloride  to  form  a  double 
argentic  and  cuprous  chloride,  which  is  soluble  in  salt  brine."  Here,  as  in  density 
reduction  by  ferric  chloride,  which  seems  at  present  to  be  the  popular  favorite,  and  by 
ferric  oxalate,  to  which  my  attention  was  but  lately  attracted,  the  principle  is  the  same. 


388        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY, 

169.  "Fog,"  or  veiling  of  the  film  is  one  of  the  most  exasperating  bugbears 
of  "dry  "work,  and  comes  without  any  premonition.  In  the  early  days  of 

There  are  one  or  two  points,  however,  insisted  upon  by  advocates  of  ferric-hyposulphite. 
Only  a  slight  rinsing  after  fixing  is  recommended,  and  a  slight  rinsing  after  each  immer- 
sion in  hypo.  "Why  not  no  rinsing  at  all  to  save  time  or  a  good  thorough  but  rapid  wash 
to  insure  regularity  of  action  ?  Where  I  have  attempted  at  the  reduction  of  negatives 
only  slightly  over-dense,  I  have  found  the  most  disastrous  results  follow  a  slight  rinsing, 
where  otherwise  I  could  calculate  the  amount  of  work  done  to  a  nicety.  On  the  other 
hand,  I  have  seen  that  with  an  abnormally  opaque  negative  a  great  deal  of  time  could  be 
saved  at  first,  by  avoiding  all  washing,  and  simply  popping  the  negative  momentarily 
into  the  hypo,  for  it  does  not  take  long  to  dissolve  chloride  of  silver  either  by  ferric  hypo- 
sulphite or  by  sodiom  hyposulphite  and  back  into  the  ferric  salt.  Again,  with  ferric 
chloride  (or  oxalate)  where  strong  and  rapid  in  its  action,  a  comparatively  thorough 
washing,  though  by  no  means  habitually  insisted  on,  may  save  the  picture  a  shock  which 
will  take  all  the  pluck  out  of  it,  and  leave  it  weak  for  life. — HUGH  BREBNER. 

Local  reduction  is  done  by  chemicals,  and  these  being  liquids,  it  is  very  difficult  to 
keep  them  from  overrunning — overflowing  the  parts  to  be  reduced  and  very  often  more 
mischief  than  benefit  is  the  result. 

I  have  often  tried,  and  with  good  effect,  simply  grinding  the  too  dense  parts,  after 
drying  the  plate,  with  some  soft  grinding  powder ;  such  for  instance  as  is  used  to  "matt" 
varnished  negatives  for  retouching  purposes.  With  some  patience  the  most  obdurate 
parts  may  be  subdued  into  good  printing  condition.  Wipe  away  the  grinding  powder 
when  it  has  become  dark  and  use  fresh. 

Some  negatives  when  developed  in  a  too  often  used  developer  will  show  a  dark  deposit 
after  drying.  This  is  certainly  a  fault,  but  one  which  can  be  turned  to  advantage.  The 
local  reduction  in  these  cases  will  clear  and  clean  the  two  intense  spots  by  means  of  an 
often  renewed  tuft  of  cotton — dry,  of  course,  as  all  these  suggestions  are.  —  KARL 
KLAUSER. 

169.  General  Fog. — By  general  fog  we  mean  the  fog  produced  during  development, 
and  is  caused  by  the  partial  reduction  of  the  silver  salt  all  over  the  film.  This  is  prob- 
ably due  to  the  decomposition  of  the  gelatine  by  long  cooking,  the  products  of  which  in 
the  presence  of  a  developer  are  apt  to  react  on  the  silver  salt  and  produce  a  partial 
reduction  in  it.  The  production  of  this  kind  of  fog  and  electrical  disturbance  in  the 
atmosphere  are  apt  to  go  together.  In  unfavorable  weather  a  few  drops  of  a  saturated 
solution  of  salicylic  acid  should  be  added  to  the  gelatine  during  boiling  or  prolonged 
emulsification ;  this  will  generally  check  or  entirely  prevent  the  decomposition.  An 
excess  of  silver  is  likewise  very  likely  to  produce  the  evil,  but  the  presence  of  iodide  in 
the  emulsion  will  almost  certainly  cure  it.  Another  fruitful  source  of  fog  is  the  light 
admitted  to  the  plates  during  preparation  or  development.  The  light  should  be  tested 
by  putting  a  plats  in  the  dark  slide,  and  drawing  up  half  the  front  and  exposing  the 
half  plate  to  the  light  for  ten  minutes.  If  the  fog  be  due  to  this  cause,  the  plate  on 
development  is  sure  to  show  it  by  an  increased  reduction  of  metallic  silver  in  the  part 
so  exposed. 


NEGATIVE-MAKING  —  DRY.  389 

bromo-gelatine,  this  disease  almost  drove  the  most  optimistic  advocates  of  the 
process  from  the  contest.     A  careful  investigation  of  the  causes  was  followed 

Whatever  may  be  the  cause  of  fog — whether  the  emulsion  itself  be  in  fault,  or  whether 
the  plates  have  seen  light — we  have  found  that,  as  in  the  collodio-bromide  process,  there 
is  one  -certain,  sure  cure.  If  the  emulsion  be  at  fault,  squeeze  it  into  water  containing 
ten  grains  of  potassium  bichromate  to  each  ounce,  and  allow  it  to  rest  for  an  hour,  and 
then  wash  again  for  a  couple  of  hours  more.  If  all  the  bichromate  be  not  taken  out  by 
this  washing,  it  is  not  of  much  consequence;  since,  when  dry,  it  is  inactive.  The  sensi- 
tiveness after  this  treatment  is  not  much  diminished,  and  the  negatives  taken  with  it  are 
beautifully  bright.  Plates  may  be  treated  in  precisely  the  same  manner,  and  give  un- 
veiled pictures.  There  is  a  slight  diminution  of  sensitiveness  if  the  bichromate  be  not 
all  washed  out,  but  nothing  to  hurt,  except  where  very  great  rapidity  is  required. 

Another  cure  is  the  addition  of  a  few  grains  of  cupric  chloride.  This  diminishes  the 
sensitiveness  slightly,  but  is  most  effectual,  the  negatives  yielding  bright  and  brilliant 
images.  A  remarkable  fact  about  the  addition  of  the  cupric  chloride  is  that  the  gray 
form  of  bromide  is  converted  into  the  red  form  if  much  of  the  copper  salt  be  employed. 
The  addition  of  a  few  grains  of  ferricyanide  of  potassium  with  a  little  bromide  of  potas- 
sium is  also  a  perfect  cure,  but  this  slows  the  emulsion. 

Red  Fog. — I  know  very  little  about  this  disaster,  but  it  is  found  to  occur  if  the  silver 
nitrate  is  in  excess  of  the  salts  with  which  it  should  combine.  Cyanide  will  sometimes 
eliminate  it  from  a  film,  but  this  remedy  must  be  used  with  caution. 

Green  Fog. — This  fog  is  due  to  decomposed  gelatine  and  oxidized  pyrogallic  acid. 
Green  by  reflected  light,  it  is  pink  by  transmitted  light,  being  dichroic.  This  at  once 
points  to  the  fact  that  the  fog  is  somewhat  of  the  nature  of  a  dye,  and  every  oxidizing 
agent  ought  to  destroy  it.  In  some  cases  we  have  immersed  the  film  in  a  strong  solution 
of  bichromate  of  potash,  and,  on  afterwards  washing,  the  fog  has  disappeared;  but 
whether  it  is  a  certain  cure,  we  hesitate  to  say — it  is,  at  any  rate,  worth  trying. — CAPT. 
ABNEY. 

Pink,  red,  and  green  fog  are  much  the  same  thing,  only  in  different  stages,  and  may 
easily  be  caused  by  forced  or  prolonged  development.  The  unhealthy  look  of  these 
negatives  is  all  that  condemns  them;  prints  from  such  have  more  sparkle  and  richness  of 
shadow  than  from  negatives  quite  clear.  A  great  deal  has  been  written  on  green  fog, 
but  no  satisfactory  solution  is  to  the  fore  as  yet.  A  plate  showing  strongly  of  green  fog 
can  be  cleared  by  allowing  it  to  stay  a  long  time  in  the  hypo;  but  the  remedy  is  worse 
than  the  disease,  as  it  turns  the  plate  to  a  sickly  brown  color.  Surface  fog  or  veiling 
may  be  put  down  to  the  emulsion.  Either  it  has  had  a  touch  of  light,  or  been  heated 
too  long  in  the  manufacture,  or  has  been  prepared  with  an  excess  of  silver.  At  times 
the  coating  on  the  plates  is  so  thin  as  to  lead  one  to  think  the  shadows  were  veiling 
during  development.  Plates  so  coated  need  scientific  development  to  produce  good 
results.— JAMES  BALMAN. 

A  Method  to  Remove  the  Fog  of  Oxalate  of  Lime  from  the  Surface  of  Plates. — For  the 
baths  and  washings,  use  ordinary  water;  then,  after  fixing,  plunge  the  plate  in  a  bath  of 
ordinary  water,  100  parts;  ferrous  sulphate,  20  parts;  alum,  8  parts;  tartaric  acid,  2 


390          WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

by  the  subversion  of  the  trouble  in  usual  cases.  But  fog  still  comes  to  all,  and 
must  be  met  heroically. 

170.  Another  one  of  the  common  annoyances  is  "  frilling."  Its  equivalent 
in  animal  nature  is  the  kicking  of  the  mule,  and  the  effect  upon  the  human 
system  is  about  the  same.  You  may  use  the  utmost  care  in  every  particular 
until  you  come  to  the  fixing  of  the  plate  even,  when,  for  some  cause  you  cannot 

parts.  The  fog  rapidly  disappears,  and  then  wash  in  ordinary  water.  This  process  will 
be  especially  useful  for  plates  to  be  used  for  making  projections. — M.  C.  SIMON. 

170.  It  is  only  in  summer  that  the  trouble  comes  to  me.  I  have  traced  the  cause  to 
this  origin,  and  have  come  to  this  conclusion :  that  they  are  solely  due  to  excessive  tem- 
perature of  the  weather,  or  the  atmosphere  of  the  coating-room,  or  the  emulsion  being 
too  hot  while  coating. 

Also,  if  the  second  portion  of  gelatine  (which  should  not  be  more  than  necessary  for 
its  dissolution)  be  too  hot  when  the  boiled  portion  is  mixed  with  it,  frilling  is  almost 
certain  to  result.  We  will  suppose  you  use  good  gelatine  only.  I  use  Swiss,  and  find  it 
very  reliable.  In  summer  I  would  advise  that  the  coatings  be  done  early  in  the  morning, 
before  sunrise.  The  glass  must  be  slightly  warm;  or,  perhaps  better,  to  be  exact,  the 
temperature  of  the  emulsion,  say  100°  F.,  or  as  near  that  as  possible. 

Now  suppose  frilling  occurs,  some  advise  alum  as  a  remedy.  I  have  found  alum  a  very 
poor  help  at  best.  I  have  lately  had  a  valuable  negative  frill  after  fixing,  and  for  a 
while  the  total  destruction  of  the  negative  was  threatened.  Alum  would  not  save  it.  I 
was  in  a  quandary  for  a  few  minutes,  when  a  bright  idea  occurred  to  me.  I  flowed  over 
the  plate  several  times  with  strong  alcohol,  and  dried  it  rapidly.  The  blistering  settled 
firm,  and  allowed  the  plate  to  be  afterward  washed  and  strengthened.  I  have  since 
experimented  with  the  batch,  to  find  out  the  best  remedy  in  case  the  plates  would  frill. 
The  best  way  I  have  yet  found  is  this: 

Before  developing,  run  a  stick  of  paraffine  round  the  edges.  This  keeps  water  from 
getting  under  the  film.  After  developing,  rinse  a  little,  and  immerse  in  the  alum  bath 
for  a  few  minutes,  say  five  or  ten,  then  rinse  again  and  allow  it  to  dry ;  or,  better,  hasten 
its  drying  by  alcohol.  After  it  is  once  dry  it  can  be  again  washed,  fixed,  and  intensified 
without  the  blisters  or  frill  reappearing.  , 

I  have  made  a  good  many  plates  for  my  own  use,  and  when  the  above  precautions  in 
making  the  plates  are  adhered  to,  frilling  never  occurs. — RANALD  DOUGLAS. 

Frilling. — What  is  meant  by  frilling  is  the  gelatine  film  leaving  the  glass  plates  in 
folds  or  wrinkles,  and  a  greater  nuisance  than  this  cannot  be  met  with.  It  is  generally 
met  with  when  fixing  the  plate,  though  we  have  sometimes  met  with  it  during  the  devel- 
opment, especially  in  hot  weather.  We  will  endeavor  to  state  the  causes  of  frilling  as 
they  are  known.  Frilling  is  often  caused  by  the  use  of  unsuitable  gelatine,  possessing 
but  little  tenacity.  The  more  the  qualities  of  gelatine  are  like  glue,  the  less  chance 
there  is  of  meeting  with  this  vexatious  evil.  If  gelatine,  however,  were  like  glue  in 
respect  to  hardness,  the  difficulty  of  developing  a  plate  would  be  very  great,  since  it  is 
too  hard.  To  meet  this  objection,  a  certain  proportion  of  a  less  tenacious  gelatine  is 
mixed  with  the  harder  kind,  a  very  good  index  of  the  tenacity  being  the  temperature  at 


NEGATIVE-MAKING  —  DRY.  391 

imagine,  the  film  will  begin  to  corrugate  and  swell  and  rise  in  ridges  from 
the  glass,  and  you  are  surprised  and  baffled.  There  seems  to  be  no  universal 
preventive,  for  sometimes  the  cause  cannot  even  be  guessed  at.  There  is  some 
knowledge  on  the  subject,  however,  and  it  has  been  gathered  together  for  the 
notes. 

which  it  melts  after  swelling.  The  addition  of  chrome  alum  to  an  emulsion  also  pre- 
vents it  to  a  great  extent.  The  objections  to  chrome  alum  are  that  it  increases  the 
tenacity  of  the  gelatine  and  prevents  easy  development,  hence  it  should  be  used 
sparingly. 

Gelatine  that  has  been  cooked  for  a  long  time  has  a  special  tendency  to  frill,  and 
unless  fresh  gelatine  be  added  to  the  emulsion,  in  some  cases  the  frilling  is  inevitable. 
Long  cooking,  in  warm  weather  particularly,  means  decomposition  of  the  gelatine,  and 
decomposed  gelatine  is  very  detrimental  in  preparing  a  dry  plate.  Boiling  for  a  short 
time  has  much  the  same  effect  on  the  gelatine  as  cooking  at  a  lower  temperature,  hence 
to  avoid  frilling  it  is  better  on  the  whole  not  to  boil  the  emulsion  with  the  full  amount 
of  gelatine. 

Another  source  of  frilling  is  the  plate  being  improperly  cleaned.  If  water  will  not 
flow  in  a  uniform  sheet  from  a  plate,  it  may  be  well  understood  that  there  will  be  but 
little  adhesion  between  it  and  an  aqueous  solution  of  gelatine.  This  we  believe  to  be 
one  fruitful  source  of  the  evil. 

Another  source  of  frilling  is  unequal  drying.  Thus,  if  plates  be  dried  in  an  unventi- 
lated  box,  it  will  usually  be  found  that  a  central  patch  refuses  to  dry  till  long  after  the 
outsides  are  completely  desiccated.  At  the  junction  of  this  central  patch  with  the 
neighboring  gelatine,  frilling  is  to  be  looked  for.  It  will  spread  to  the  parts  which  have 
been  longest  in  drying.  This  is  due  to  a  false  tension  set  up  in  the  film,  and  can  only 
be  conquered  by  drying  the  plate  by  means  of  alcohol  or  by  using  a  proper  drying  cup- 
board. 

Again,  when  plates  are  coated  in  hot  weather,  unless  precautions  are  taken,  they  take 
long  to  set.  The  emulsion  remains  liquid  on  the  plate  for  sufficient  time  to  allow  the 
heavier  particles  of  silver  bromide  to  settle  down  on  the  surface  of  the  glass.  This,  of 
course,  diminishes  the  surface  to  which  adhesion  can  take  place.  We  believe  that  most 
of  the  frilling  which  takes  place  in  plates  prepared  in  hot  weather  may  be  traced  to  this 
cause.  When  washing  after  fixing,  frilling  is  often  caused  by  allowing  a  stream  of 
water  from  the  tap  to  impinge  on  the  plate.  This  should  never  be  allowed  if  the  film  is 
at  all  delicate. 

•Chrome  alum  is  recommended  to  prevent  frilling  when  soft  gelatine  is  used  in  hot 
weather.  Plates  which  frill  or  blister  will  not  show  any  signs  of  so  doing  if  kept  for  a 
few  months. 

A  general  remedy  for  frilling  is  to  coat  the  plate  with  normal  collodion  containing 
about  six  grains  of  tough  pyroxyline  to  the  ounce  of  solvents.  The  formula  would  be 
thus:  Tough  pyroxyline,  6  grains;  alcohol  (0.820),  \  ounce;  ether  (0.725),  £  ounce. 

This  may  be  applied  to  the  film  immediately  before  developing  the  plate;  the  solvents 
are  washed  away  in  a  dish  of  clean  water  first,  and  when  all  repel lant  action  is  gone, 


392        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

171.  Yellow  stains;  silver  stains;  developer  stains;  stains  which  come 
before,  during,  and  after  the  manipulations,  have  had  a  great  deal  of  attention. 
Some  of  the  causes  are  known  and  remedies  are  found.  Some  are  as  much  a 
mystery  as  ever.  Frequently  yellow  spots  appear,  large  and  small,  after 

the  developing  solution  is  applied.  If  the  film  has  been  allowed  to  dry,  a  solution  of 
one  part  of  ether  to  three  of  alcohol  will  render  it  pervious  to  the  developing  solutions. 
In  some  batches  of  plates  frilling  is  so  obstinate  that,  although  collodion  is  applied,  the 
film  has  a  tendency  to  curl  off  from  the  edges  of  the  plate.  It  is  advisable,  where  such 
is  suspected,  to  run  a  brush  with  an  India-rubber  solution  round  the  edges,  to  prevent 
the  water  having  access  to  that  part  of  the  film.  When  fixing  such  plates,  it  not  unfre- 
quently  happens  that  blisters  appear,  and  if  they  are  allowed  to  remain  as  they  were, 
they  will  spoil  the  negative.  To  avoid  this,  wash  the  plate  under  the  tap  until  all  the 
blisters  join.  By  a  prick  at  one  corner  then  let  the  liquid  free,  and  continue  washing. — 
CAPT.  ABNEY. 

171.  The  question  has  often  been  asked,  "How  can  the  yellow  stains  in  negatives, 
sometimes  caused  by  intensifying  them  with  mercury,  be  removed?  "  And  up  to  this 
time  I  am  not  aware  that  it  has  been  satisfactorily  answered. 

It  has  been  recommended  to  change  all  the  silver  in  the  negative  into  the  chloride, 
and  redevelop.  My  attempts  to  remedy  the  trouble  by  this  method  have  not  been  suc- 
cessful. The  yellow  stain  persists  in  coming  back,  after  all.  This,  it  seems  to  me. 
might  be  expected.  For  what  is  the  substance  of  the  stain  ?  Probably,  sulphide  of 
mercury,  and,  perhaps,  sulphide  of  silver  from  the  decomposition  of  the  hyposulphites 
of  silver  and  sodium  remaining  in  the  gelatine.  It  is  not  easy  to  convert  either  of  these 
sulphides  into  chlorides  in  the  film.  I  will  not  say  it  is  impossible,  but  I  have  not  suc- 
ceeded in  removing  the  stain  in  this  way. 

I  shall  now  describe  an  experiment  of  mine,  which  is  given  for  what  it  is  worth,  for  I 
have  not  had  an  opportunity  to  repeat  it. 

A  large  pan,  sitting  at  one  side  in  an  out-of-the-way  place,  contained  an  old  hypo 
solution  in  which  hundreds  of  8  by  10  wet-plate  negatives  had  been  fixed,  having  been 
replenished  often  by  the  addition  of  the  hot  baths  used  for  fixing  prints,  as  well  as  those 
which  had  served  out  their  time  for  dry  plates.  Not  having  been  used  for  some  time, 
the  solution  had  partially  evaporated  and  changed  into  a  mass  of  crystals.  Of  what 
these  crystals  are  composed,  it  would  be  interesting  to  know  precisely.  How  much 
hyposulphite,  trithionate,  tetrathionate,  double  hyposulphite  of  silver  and  sodium,  etc., 
they  contain,  would  be  a  nice  question  to  be  solved  by  analysis.  It  is  sufficient  at  present 
to  say  that  some  of  the  clear  crystals  were  taken  out  and  dissolved,  and  the  solution 
proved  to  be  a  first-rate  fixing  bath  for  negatives. 

This  was  not  all.  Among  a  number  of  negatives  made  one  day  last  week,  one  was 
found  next  morning  to  .need  intensifying.  After  applying  the  mercury  and  following 
with  ammonia  (on  the  wrong  presumption  that  the  washing  had  been  sufficient),  one  of 
the  worst- stained  specimens  ever  likely  to  be  seen  was  brought  forth.  I  reckoned  my 
negative  to  be  beyond  the  reach  of  human  skill.  It  was  a  goner,  sure.  To  see  what 
further  would  happen,  I  slipped  it  into  the  said  fixing  bath,  and  left  it  to  its  fate  from 


NEGATIVE-MAKING  —  DRY.  393 

drying.  It  is  believed  that  during  fixation  the  hyposulphite  creeps  in  through 
punctures  in  the  film  and  cannot  be  removed  by  any  amount  of  washing — it 
cannot  be  reached  unless  the  film  is  removed  and  both  sides  washed.  Enough 
water  follows  to  diffuse  this  even  small  amount  of  hypo  between  film  and  glass 

Saturday  until  Monday.  I  had  been  surprised  when  it  came  from  the  ammonia  stained, 
streaked,  and  blotched,  but  on  taking  it  from  the  above  solution  I  could  hardly  believe, 
what  was  nevertheless  true,  that  every  blotch  and  stain  had  entirely  disappeared  and  the 
negative  was  as  clean  and  clear  as  ever. 

What  does  this  fable  teach? 

First,  the  crystals  from  an  old  hypo  solution  may  be  utilized  for  fixing  negatives. 
Probably  a  large  part  of  the  silver  remains  in  the  mother-liquor  as  sediment.  And, 
second,  if  the  solution  obtained  as  above  described  continues  to  perform  as  in  the  case 
related,  it  will  be  found  to  be  the  easiest  and  best  way  for  removing  the  yellow  stains 
caused  by  mercurial  intensification. 

The  stains  were  not  superficial,  as  may  be  surmised.  The  plate  was  thoroughly  rubbed 
with  'the  hand  under  the  tap. — W.  H.  SHERMAN. 

To  remove  silver  stains  from  a  gelatine  negative,  then,  having  caught  a  stained 
negative,  proceed  as  follows:  Kemove  varnish  thoroughly,  and  then  wash  all  the  spirits 
out  of  the  film,  and  having  prepared  the  following  solution,  immediately  before  use  pour 
over  the  negative,  and  keep  your  eye  upon  it,  moving  backward  and  forward  until  stains 
disappear,  which  will  take  from  five  till  fifteen  minutes,  according  as  the  stains  have 
been  longer  or  shorter  in  the  film : 

A.  Sulphocyanide  of  ammonia,  £  drachm ;  water,  1  ounce. 

B.  Nitric  acid,  J  drachm ;  water,  1  ounce. 

The  crystals  of  sulphocyanide  should  be  used,  and  a  fresh  solution  made  for  every 
negative,  as  when  it  is  made  up  in  solution  it  loses  its  strength.  A  and  B  must  be  made 
up  separately,  and  added  the  one  to  the  other.  On  no  account  must  the  nitric  acid  be 
added  to  the  ammonia  without  the  admixture  of  water,  or  hydrocyanic  acid  fumes  will 
be  given  off,  which  are  exceedingly  poisonous ;  but  with  the  addition  of  water  the  action 
is  much  slower,  and  no  inconvenience  is  felt  on  this  score. 

The  stains  having  been  removed,  have  ready  a  saturated  solution  of  chrome  alum,  and 
after  taking  the  negative  out  of  the  stain  remover,  place  it  in  the  alum  to  harden  the  film 
and  prevent  blistering,  after  which  wash,  dry,  varnish,  and  print  as  usual.  The  solution 
acts  on  nothing  but  the  spots,  and  there  need  be  no  fear  of  its  reducing  the  negative,  the 
only  change  being  to  turn  a  yellow  negative  to  a  bluish  tint. — DANIEL  ROBERTSON. 

No  spots  I  have  seen  are  so  aggravating  as  the  opaque  kind.  To  think  of  and  compose 
a  picture  to  one's  satisfaction  (if  ever  it  is  done),  and  then  find  the  negative  pitted  with 
these  spots,  often  causes  one  to  lose  their  moral  tone  for  the  time  being.  I  know  of  no 
certain  remedy  for  such,  unless  it  be  a  slight  rubbing  by  the  finger,  which  may  remove 
them  before  drying. 

The  spots  I  have  called  pits  are  not  met  with  so  frequently  now  as  formerly.  Makers 
are  bringing  their  plates  to  such  a  pitch  of  rapidity  by  increased  heat  applied  to  the 
emulsion,  or  otherwise,  that  it  tends  to  dispel  them.  . 


394        WILSON'S  QUARTER  CENTURY  ix  PHOTOGRAPHY. 

and  cause  the  yellowness  so  fatal  to  good  negatives.  There  seems  to  be  no 
hope  for  a  negative  thus  afflicted.  There  are  red  spots,  too,  which  make  the 
heart  sick. 

Clear  spots  that  are  not  caused  by  abrasion  of  the  film,  are  mostly  due  to  impure 
chemicals.  Very  often  the  alcohol  is  at  fault ;  they  show  more  in  plates  made  by  any  of 
the  ammonia  nitrate  processes,  but  sometimes  the  appearance  of  large  patches,  irregular 
in  form,  and  transparent,  would  lead  one  to  suppose  that  the  particular  patch  was  insen- 
sitive. I  can  give  no  plausible  solution  as  to  the  why  and  wherefore. 

But  by  far  the  most  troublesome  of  plague  spots  is  the  opaque  spot ;  it  seldom  can  be 
eradicated,  whilst  the  clear  spot  may  in  a  measure  be  remedied,  with  time  and  care,  by 
delicate  spotting. 

Stains  very  often  can  be  traced  to  the  glass,  and  if  examined  closely,  the  explanation 
will  probably  be  found  in  the  thumb-  and  finger-marks  underneath  the  film.  I  do  not 
mean  to  imply  that  all  stains  arise  from  handling  the  glass  with  dirty  fingers ;  a  bad 
quality  of  glass  may  be  used  that  has  impurities  in  itself,  and  makers  cannot  be  too 
careful  in  their  selection  of  good,  clean,  and  even  glass.  Dry  plates  are  made  at  so  low 
a  figure  nowadays  that  it  is  imperative  that  cheap  glass  should  be  used,  bringing  with  it 
the  usual  amount  of  blisters,  bells,  scratches,  etc. 

Stains  also  arise  from  the  wrapping  papers,  and  by  the  careless  manipulation  of  the 
plate  during  development  and  subsequent  treatment,  which  only  show  upon  the  drying 
of  the  plate.  But  this,  being  entirely  under  the  control  of  the  operator,  can  hardly  be 
called  a  defect  in  the  plate. — JAMES  BALMAN. 

Our  experience  with  gelatine  negatives,  especially  when  they  have  been  strengthened, 
is  that  they  may  look  beautiful  and  clear  when  looked  through,  but  when  printed  copies 
are  made  from  them  there  appear  ominous  spots  upon  the  paper,  which  necessitate  a 
good  deal  of  touching  up  to  make  them  presentable.  This  consuming  valuable  time, 
is  a  great  drawback  to  the  photographer,  especially  when  a  great  number  of  copies  is 
needed.  .  r 

Now,  if  such  a  negative  is  carefully  examined  we  shall  perceive  weak  spots  of  a  yellow 
color  corresponding  to  the  white  spots  upon  the  printed  copies.  No  doubt,  as  some  have 
remarked,  these  spots  are  to  be  traced  to  the  insufficient  washing  of  the  negatives,  which 
make  their  appearance  on  intensifying,  the  hypo  not  being  thoroughly  eliminated  from 
the  film.  Or  it  may  arise  from  imperfect  fixing,  or  in  not  sufficiently  moving  the 
intensifying  fluid  during  the  process  of  strengthening,  causing,  in  addition  to  these  spots, 
cloudiness. 

Sufficient  care,  of  course,  will  prevent  the  occurrence  of  such  phenomena,  but  in 
practice  it  is  not  always  convenient  to  work  undisturbed  upon  any  one  subject,  and  when 
the  spots  do  come  it  is  well  to  be  able  to  know  how  to  attack  them.  Moreover,  when 
the  originals  from  which  the  negatives  are  taken  are  weak,  it  is  often  necessary  to  subject 
the  negative  to  a  sort  of  inquisition — to  torture  it  until  it  becomes  better  and  has  the 
requisite  strength.  Now,  these  processes  frequently  give  the  negatives  a  color  and  tone 
so  very  bad  for  copying  purposes,  that  any  means  to  improve  them  will  be  thankfully 
received. 


NEGATIVE-MAKING — DRY.  395 

172.  Spots  on  gelatine  negatives  are  also  caused  by  "tear-drops/7  the  result 
of  unequal  drying.  If  the  manipulator  will  form  the  habit  of  watching 
whether  such  a  nuisance  is  liable  to  occur  or  not,  before  the  negative  is  dry 

Now,  let  me  here  say,  in  treating  such  spotty  negatives  the  process  of  changing  them 
to  a  chloride  of  silver  is  of  the  highest  value,  inasmuch  as  the  spots  will  entirely  disap- 
pear. Proceed  in  the  following  manner :  The  intensified  or  not  intensified  negative  is 
laid  dry  in  a  dish  and  covered  with  the  following  solution :  Five  per  cent,  alum  solution, 
1  litre;  bichromate  of  potassa,  10  grains;  chemically  pure  hydrochloric  acid,  20  grains. 
These  chemicals  may  be  dissolved  in  pure  water  instead  of  the  alum  solution,  but  then 
there  is  danger  of  producing  frills  from  the  acid. 

Allow  the  negative  to  remain  in  this  solution  until  it  becomes  thoroughly  yellow, 
which  usually  occurs  in  a  few  minutes.  Wash  next  thoroughly  under  a  cock  until  it 
becomes  colorless  and  when  looked  through  appears  gray.  Next  carry  the  negative  into 
the  light  room,  or,  best  of  all,  in  the  sun,  and  let  it  be  exposed  a  few  minutes.  If  now 
the  chloro-silver  image  is  laid  in  the  oxalate  developer  it  will  become  black  in  a  few 
minutes,  because  it  is  reduced  to  the  metallic  state,  and  all  the  green  spots  will  disappear. 
The  subsequent  washing  is  effected  in  a  quarter  of  an  hour. 

The  chloride  of  silver  solution  gradually  weakens,  and,  in  consequence,  works  slower 
and  slower,  or  not  at  all,  in  time ;  but  it  may  be  freshened  up  by  the  addition  of  bichro- 
mate of  potassa  and  muriatic  acid. 

Although  the  transformation  of  a  silver  image  into  a  chloride  of  silver  image  is  not 
exactly  new,  I  have  not  found  it  to  be  a  process  generally  employed,  but  I  think  such 
remarks  will  not  be  found  superfluous. — L.  BELITSKI. 

172.  In  making  some  washed  emulsion,  I  found  my  plates 
"afflicted"  by  a  species  of  tear  drops  which  formed  near  the 
lower  edges,  as  shown  by  Fig.  329. 

An  idea  came  into  my  mind  that  it  might  be  caused  by 
the  cold  produced  by  the  evaporation  of  the  ether.  Under 
this  inspiration  I  prepared  two  plates  under  the  same 
conditions — that  is  to  say,  the  weather  was  very  bad,  the 
painted  walls  of  the  house,  as  it  were,  running  with  water. 
In  a  quarter  of  an  hour  I  visited  my  plates;  water  was  run- 
ning down  the  front  as  well  as  the  back  of  the  glass;  the 
ether  preventing  its  passage,  compelled  it  to  take  a  zigzag 
form  on  the  collodionized  surface;  this  is  what  caused  the 
ramifications.  In  fact,  my  advice  is,  never  to  prepare  washed 
emulsion  plates  excepting  in  a  very  dry  place.  I  firmly 
believe  that  much  failure  attending  washed  emulsion  plates 
is  due  to  this  not  unknown  but  unobserved  cause.  Any  one 
can  make  an  experiment  of  this  by  covering  a  glass  plate 
with  ordinary  collodion,  and  placing  it  against  a  wall  in  a  damp  place  to  dry;  in  two 
or  three  minutes  the  phenomenon  will  have  made  its  appearance.  Now  that  the  cause  is 
found,  the  cure  is  easy. — LEON  VIDAL. 


396         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

after  washing,  it  may  be  prevented  entirely  by  a  second  slight  treatment  under 
the  tap.  Some  brands  of  plates  are  apt  to  dry  unequally,  and  with  such  the 
tear-drops  are  most  liable  to  make  their  appearance.  Bad  washing  and  want 

Tear-drops  on  gelatine  negatives  may  be  prevented  by  wiping  off  the  surplus  water 
from  the  face  of  the  negative  before  setting  it  aside  to  dry,  either  with  a  squeegee  or  a 
tuft  of  cotton,  or  any  other  convenient  thing. 

Should  a  negative  get  spotted  from  uneven  drying,  put  it  again  in  water,  and  be 
careful  to  wipe  the  water  off  this  time  before  setting  it  aside  to  dry,  and  it  will  be 
entirely  free  from  any  previous  marking ;  tear-drops  have  a  tendency  to  form  upon  some 
plates,  but  with  this  precaution  observed  they  will  never  occur. 

Brown-yellow  stains  coming  upon  negatives  after  they  have  been  used  a  short  time 
are,  if  in  the  film,  and  not  on  it,  from  lack  of  fixing.  If  a  speck  in  a  negative  should 
seem  to  hang  back,  and  not  fix  like  the  rest  of  the  plate,  unless  special  precaution  be 
taken  with  this  plate  a  stain  is  almost  sure  to  appear  on  this  spot,  sooner  or  later.  In 
such  a  case  wash  the  plate  for  five  minutes  or  so  after  it  seems  to  be  fixed,  then  place 
it  back  again  for  a  few  minutes  into  the  fixing  solution,  or,  better  still,  pour  over  it  an 
almost  saturated  solution  of  new  hypo.  This  will  invariably  clear  off  the  most  stubborn 
case.  The  spots  that  are  slow  to  fix  are  from  too  thickly  coated  parts  of  the  plate, 
antf  when  they  remain  in  the  soda  for  a  long  time  the  pores  of  the  film  become  close  and 
impermeable  to  the  fixing  solution,  but  are  immediately  opened  again  when  put  into 
water,  and  will  fix  as  readily  as  at  first,  when  put  back  into  the  soda. — JAMES  INGLIS. 

It  sometimes  happens  that  gelatino-bromide  negatives  after  a  certain  time  are  covered 
with  a  white  powder  produced  by  two  causes:  first,  bad  washing;  and,  secondly,  deterio- 
ration of  the  varnish.  I  prefer,  instead  of  varnishing  the  negatives,  to  keep  them  for  a 
half  hour  in  an  alum  bath  after  the  last  washing,  after  which  I  again  wash  them  and  give 
them  an  alcohol  bath.  If  the  white  dust  forms  on  our  negatives,  here  is  the  remedy 
which  we  have  always  found  successful: 

1st.  Expose  the  negatives  to  the  sun,  and  carefully  remove  with  a  chamois  the  dry  dust 
that  covers  the  film. 

2d.  Wash  the  negatives  in  ordinary  alcohol  for  a  quarter  of  an  hour,  and  allow  them 
to  dry. 

The  best  means  of  avoiding  these  accidents  is  to  greatly  prolong  the  washings,  which 
are  almost  always  insufficient.  After  the  last  washing,  plunge  the  plate  into  alcohol  for  a 
half  hour  and  allow  it  to  dry.  If  the  washing  in  water  has  not  been  sufficient,  the 
washing  in  alcohol  removes  the  last  traces  of  hyposulphite,  and  makes  the  negatives 
remarkably  pure  and  clean.  Use  the  same  process  for  strengthened  negatives.  Washing 
in  alcohol  has  also  the  advantage  of  accelerating  the  desiccation,  a  very  important  thing 
in  winter  especially.  The  gelatine  negatives  should  always  be  kept  in  a  perfectly  dry 
place,  and,  instead  of  keeping  them  in  grooved  boxes,  they  should  be  piled  up,  having  a 
thin  sheet  of  white  paper  between  them.  In  this  condition,  being  removed  from  atmos- 
pheric influence,  they  are  much  less  apt  to  spoil.  It  sometimes  happens  that  in  taking 
the  picture  of  a  monument  there  is  a  want  of  contrast,  either  because  the  sun  is  hidden, 
or  from  some  other  cause.  In  this  case  the  insufficiency  may  be  supplied  by  stopping 


NEGATIVE-MAKING    -DRY.  397 

of  washing  bring  many  a  trouble  which  might  as  well  have  been  avoided,  and 
frequently  cause  a  grievous  deterioration  of  quality  in  the  negative. 

173.  And  with  all  these  the  chapter  on  hitches  is  not  ended.     No  one  has 

the  development  when  all  the  details  have  shown  themselves,  and  strengthening  with 
bichloride.  The  strengthening  gives  rather  a  hard  tone,  but  this  is  an  advantage  when 
the  contrasts  are  wanting  and  the  negatives  are  flat. — CHEVALIER  O'MADDEN. 

173.  In  working  with  gelatine  emulsion  there  is  always  a  danger  of  chemical  or  light 
fog,  due  in  the  first  case  to  faults  in  the  preparation  or  development  of  the  emulsion,  and 
in  the  second  to  admission  of  light  during  some  portions  of  the  process. 

In  the  following  category  I  have  enumerated  most  of  the  possible  causes  of  failure 
under  the  several  processes,  commencing  from  the  coating  of  the  plates  down  to  the 
varnishing  of  the  finished  negative. 

The  Emulsion  becomes  Fluid  in  the  Bottle. — This  defect  is  often  due  to  the  want  of  an 
antiseptic,  such  as  salicylic  acid,  carbolic  acid,  thymol,  etc.,  in  the  emulsion.  The 
emulsion  under  the  circumstances  refuses  to  set.  The  setting  powers  can  be  restored  by 
the  addition  of  fresh  gelatine ;  but  the  presence  of  any  decomposed  matter  is  apt  to  give 
very  foggy  plates. 

The  Emulsion  is  Thin,  and  Permits  some  of  the  Bromide  of  Silver  to  Separate  to  the  Bottom 
of  the  Flask. — This  may  arise  from  too  small  a  proportion  of  gelatine  having  been  em- 
ployed, the  consistency  of  the  solution  being  insufficient  to  retain  the  bromide  of  silver 
in  suspension ;  or  it  may  be  due  to  a  tendency  to  decomposition.  The  remedy  in  either 
case  will  be  to  stir  in  thoroughly  fresh  gelatine  in  the  proportion  of  2  grammes  to  every 
100  c.  c.  of  emulsion. 

The  Emulsion  Tarns  Brown  and  Gray. — This  often  occurs  when  the  emulsion  has  been 
exposed  for  some  time  to  white  light,  but  the  change  will  probably  only  affect  the  surface 
of  the  emulsion,  and  the  interior  will  still  be  sensitive  and  fit  for  use. 

The  Emulsion  Flows  Irregularly  over  the  Plate.—  This  will  probably  be  due  to  the  want 
of  a  substratum.  A  weak  solution  of  water  glass  (1-200)  may  be  used,  or  a  syrup  of 
sugar  and  water,  or  albumen.  Gelatine  emulsion  will  not  flow  well  over  a  collodion 
substratum  unless  a  small  quantity  of  glycerine  (about  2  per  cent.)  is  previously  added. 

Waves  and  irregular  marks  occur  during  coating,  principally  in  winter-time,  when  the 
plates  are  too  cold,  or  the  emulsion  not  sufficiently  fluid.  The  marks  do  not  show  after 
fixing.  If  the  plates,  on  the  other  hand,  are  too  hot,  streaks  are  formed,  which  show  in 
the  finished  negative.  The  plates  should  be  slightly  warmed,  and  the  emulsion  kept  in 
water  at  a  temperature  of  about  50°  or  60°  C. 

Air-bubbles  which  form  on  the  surface  of  the  film  during  coating  can  easily  be  avoided 
by  pouring  back  the  excess  of  emulsion  into  a  separate  vessel.  The  best  form  of  vessel 
to  employ  is  an  earthenware  teapot  wrapped  up  in  a  thick  cloth. 

The  emulsion  refuses  to  set  when  poured  on  to  the  plate. 

a.  The  temperature  of  the  coating-room  may  be  too  high ;  if  so,  the  plates  should  be 
laid  after  coating  on  a  metal  plate  or  a  stone  slab,  when  they  will  set  in  a  few  minutes, 
and  the  film  will  not  melt  again  so  readily  as  it  otherwise  would. 

b.  The  proportion  of  gelatine  in  the  emulsion  may  be  deficient.    This  may  be  remedied 


398         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

confessed  as  yet  that  the  bromo-gelatine  process,  wonderful  as  its  capabilities 
and  results  are,  is  the  "  process  of  the  future,"  or  all  that  the  earnest  photog- 
rapher believes  to  be  possible  for  his  craft  to  accomplish.  There  are  great 

by  the  addition  of  2  or  8  grammes  of  fresh  gelatine  to  every  10  c.  c.  of  emulsion,  and, 
after  standing  for  a  few  hours,  the  latter  should  be  heated  to  insure  complete  solution. 

c.  The  want  of  setting  power  is  more  often  caused  by  a  decomposition  of  the  emulsion, 
consequent  on  too  long  a  boiling,  too  high  a  temperature,  injudicious  use  of  ammonia,  or 
frequent  melting  and  setting  of  the  emulsion,  which  is  especially  injurious  to  a  gelatine 
of  inferior  quality.  This  want  of  setting  power  often  gives  rise  to  frilling  and  blisters, 
which  may  be  avoided  by  the  addition  of  a  small  quantity  of  the  alum  and  glycerine 
solution. 

Spots  and  small  rings,  which  are  very  apparent  in  the  finished  negative,  are  due  princi- 
pally to  irregular  drying  of  the  plates.  The  drymg  may  have  been  prolonged  too  long 
owing  to  variations  in  the  state  of  the  atmosphere  or  temperature,  or  the  same  defect  may 
arise  from  having  the  drying-cupboard  too  hot,  and  opening  the  door  frequently  while 
the  plates  are  drying. 

Gelatine  films  which  have  been  dried  by  soaking  in  alcohol,  frequently  crack,  owing 
to  the  contraction  of  the  gelatine  being  too  rapid.  At  other  times  faint  marks  make  their 
appearance,  which  are  visible  in  the  finished  negative. 

Mildew  occurs  when  the  plates  have  been  kept  in  a  damp  place.  An  emulsion  to  which 
an  antiseptic  has  been  added  is  not  liable  to  this  defect. 

The  plates  are  very  slow  in  developing,  or  develop  irregularly,  when  they  have  been  kept 
for  a  long  time  in  a  very  dry  place.  In  developing  such  plates,  they  should  be  previously 
soaked  for  some  time  in  water.  The  emulsion  may  contain  too  much  alum  or  chrome 
alum,  in  which  case  the  addition  of  a  few  drops  of  glycerine  will  improve  its  absorptive 
power.  Such  an  emulsion  is  best  treated  with  the  pyrogallic  developer,  and  before  the 
addition  of  the  pyrogallic  acid  a  dilute  solution  of  ammonia  may  be  allowed  to  act  on 
the  plate  for  a  few  minutes.  If  the  films  are  very  hard,  they  may  be  soaked  for  a  few 
minutes  in  water  at  a  temperature  of  30°  C. 

If  the  plate,  on  fixing,  appears  fogged,  the  mistake  may  have  been  caused  by  over- 
exposure,  careless  development,  employment  of  a  faulty  emulsion,  or  admission  of  white 
light  at  some  stage  of  the  operations. 

a.  The  part  of  the  plate  protected  by  the  rebate  of  the  frame  should  be  examined ;  and 
if  this  be  free  from  fog,  the  fault  has  been  due  to  overexposure. 

6.  If,  however,  the  whole  plate  fogs  over  during  development,  we  may  suspect  that 
light  has  been  admitted.  The  camera  and  dark  slides  should  be  carefully  examined,  as 
well  as  the  connection  of  the  flange  of  the  objective  with  the  front  of  the  camera.  To 
test  the  quality  of  the  ruby  glass  employed  in  the  window  or  lantern,  half  a  gelatine  plate 
should  be  carefully  covered  over,  and  the  remaining  half  exposed  for  three  to  five 
minutes  to  the  light  passing  through  the  ruby  glass.  When  treated  with  a  fresh  de- 
veloper, both  portions  should  fix  out  quite  clear.  If  the  exposed  half  fogs  over,  while 
the  unexposed  portion  remains  clear,  the  glass  may  be  considered  unsafe. 

c.  Fog  may  be  due  to  decomposition  of  the  gelatine,  caused  either  by  cooking  the 


NEGATIVE-MAKING  —  DRY.  399 

attainments  before  us.  They  are  unveiling  every  day.  We  must  be  patient 
with  what  is  and  hope  to  do  better  with  what  comes. 

emulsion  too  long,  use  of  too  high  a  temperature,  addition  of  too  much  ammonia,  or  the 
employment,  under  certain  circumstances,  of  materials  having  an  alkaline  reaction. 
The  remedy  for  this  so-called  chemical  fog  consists  in  the  addition  of  a  few  drops  of 
tincture  of  iodine,  or  treatment  of  the  emulsion,  after  it  has  been  pressed  through  canvas, 
with  a  mixture  of  1  part  potassium  bichromate,  3  parts  hydrochloric  acid,  and  100  to  150 
parts  of  water.  After  ten  or  fifteen  minutes,  the  emulsion  is  thoroughly  washed  in  plenty 
of  water.  The  sensitiveness  is  slightly  diminished  by  such  treatment,  but  may  be 
increased  again  by  the  addition  of  a  few  drops  of  ammonia. 

d.  Fog  is  apt  to  ensue  when  plates  take  longer  than  from  three  to  six  days  to  dry.   The 
upper  part  of  the  film  remains  clear,  but  a  large  round  spot  on  the  under  side  of  the  film 
shows  the  part  which  has  been  the  last  to  dry.     As  a  remedy  against  very  slow  drying, 
Haack  recommends  sprinkling  the  drying-room  with  carbolic  acid.     Plates  which  have 
been  already  coated  and  give  fog  are  more  difficult  to  restore  than  the  solid  emulsion. 
They  may  be  laid  in  the  above  bichromate  mixture,  and  then  thoroughly  washed  and 
dried.     Another  good  plan  is  to  immerse  for  ten  minutes  in  a  solution  of  10  parts  ferri- 
cyanide  of  potassium,  10  parts  bromide  of  potassium,  and  100  parts  water,  and  to  wash 
afterward  for  some  hours. 

e.  If  the  plates  have  been  dried  at  too  high  a  temperature,  they  are  apt  to  fog  during 
development. 

f.  Plates  which  have  been  kept  for  a  long  time  in  a  damp  place  are  inclined  to  fog  and 
lose  their  sensitiveness. 

g.  Lastly,  wrapping  plates  up  in  unsuitable  material,  such  as  paper  containing  printed 
matter,  various  kinds  of  colored  paper,  tin-foil,  etc.,  induces  fog,  and  gives  rise  to  marks, 
causing  an  abnormal  reduction  of  silver  under  the  action  of  the  developer. 

Eedfog  occurs  when  an  emulsion  contains  an  excess  of  silver,  but  this  defect  is  rarely 
met  with  in  commercial  plates.  According  to  Chardon,  this  phenomenon  occurs  when 
an  emulsion  is  prepared  with  excess  of  soluble  bromide  by  pouring  the  bromized  gelatine 
into  the  silver  nitrate  instead  of  vice  versa.  An  emulsion  formed  in  this  way,  however, 
does  not  give  red  fog,  according  to  Abney,  when  developed  with  ferrous  oxalate. 

Yellow  fog  occurs  during  development  with  alkaline  pyrogallic.  It  is  due  to  the  em- 
ployment either  of  inferior  pyrogallic  acid,  too  concentrated  a  solution,  or  the  excessive 
addition  of  ammonia.  An  old,  discolored  developer  will  also  give  the  same  defect.  A 
negative  which  has  been  discolored  in  this  way  may  be  treated,  after  fixing,  with  a 
saturated  solution  of  alum  containing  hydrochloric  acid  J  per  cent,  to  1  per  cent.,  or 
with  a  weak  solution  of  potassium  cyanide.  The  acid  should  be  washed  off  as  quickly 
as  possible,  otherwise  the  film  is  likely  to  blister.  If  ferrous  oxalate  be  used  as  a  de- 
veloper, and  not  thoroughly  washed  off  before  fixing,  it  turns  the  fixing  solution  yellow, 
and  the  negative  becomes  discolored. 

Green  fog  may  be  due  to  various  causes.  Abney  mentions  a  kind  of  green  fog,  which 
is  di-chroic,  being  green  by  reflected  light,  and  pink  by  transmitted  light.  This  kind  of 
discoloration  may  sometimes  be  removed  by  soaking  the  film  in  a  solution  of  potassium 
bichromate,  but  hydrogen  peroxide  will  be  found  more  effectual. 


400        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  novice  is  oftentimes  appalled  at  the  number  of  drawbacks  possible  in 
the  practice  of  photography.  An  impression  seems  to  have  been  sent  broad- 

A  white  opalescent  veil  often  occurs  in  developing  with  ferrous  oxalate.  This  makes  its 
appearance  when  plates  are  washed  in  water  containing  lime.  The  deposit  can  be  re- 
moved with  weak  hydrochloric  acid,  but  it  is  of  no  consequence,  as  it  is  quite  transparent, 
and  cannot  be  detected  after  the  negative  is  varnished. 

The  Plates,  when  Developed  with  Ferrous  Oxalate,  become  Covered  with  a  Yellow  Deposit. — 
This  defect  occurs  when  too  large  a  proportion  of  ferrous  sulphate  is  used  in  working 
with  the  mixed  developers.  If  the  acid  potassium  salt  be  employed,  or  if  the  neutral 
salt  has  been  rendered  acid,  the  deposit  is  thrown  down  in  large  quantities. 

Clear,  undefined  spots  and  marks,  visible  after  fixing,  show  that  the  gelatine  employed 
contains  grease.  They  do  not  make  their  appearance  when  the  emulsion  has  been 
treated  with  ammonia,  and  subsequently  washed. 

/Small pinholes  are  caused  by  particles  of  dust  adhering  to  the  plate,  which  prevent  the 
light,  as  well  as  the  developer,  from  acting.  Plates  should  be  dusted  over  with  a  broad 
camel's-hair  brush  before  exposure. 

White  marks  or  round  spots  with  a  sharp  outline,  which  have  a  glossy  appearance  after 
fixing,  are  caused  by  air-bubbles  adhering  to  the  plate  during  development.  They  may 
be  avoided  by  rinsing  the  plate  in  water  previous  to  development,  or  by  keeping  the 
developer  in  gentle  motion. 

Opaque  spots  of  a  more  or  less  irregular  outline  are  due  to  a  reduction  of  silver  caused 
by  specks  of  dust  dropping  on  the  plate  during  coating  or  drying.  Gelatine  plates 
which  have  been  soaked  in  alcohol  to  accelerate  the  drying  frequently  show  these  opaque 
spots. 

Irregular  zig-zag  lines  are  caused  when  stoppages  have  occurred  in  the  flow  of  the 
developer.  Soaking  the  plates  for  a  short  time  in  water  assists  the  flow  of  the  developer. 

The  Image  is  Foggy. — This  is  generally  due  to  overexposure,  or  to  the  development 
having  been  forced  by  addition  of  ammonia,  without  a  corresponding  amount  of  potas- 
sium bromide. 

The  picture  is  harmonious,  but  wanting  in  density,  when  too  weak  a  developer  has  been 
employed.  An  increase  in  the  strength  of  the  developer  will  always  be  found  a  remedy 
when  the  emulsion  itself  is  in  fault.  This  defect  is  more  apparent  when  the  emulsion 
contains  iodide  of  silver,  nitric  acid,  or  potassium  cyanide,  than  when  bromide  of  silver 
alone  is  present.  It  may  often  be  due  to  the  films  being  too  thin,  or  the  emulsion  being 
too  poor  in  silver. 

The  Picture  is  Hard,  and  Wanting  in  Detail. — This  is  generally  due  to  underexposure, 
to  want  of  sufficient  ammonia  in  the  developer,  or  to  the  employment  of  too  much  bro- 
mide of  potassium.  Underexposure  is  difficult  to  remedy  in  the  case  of  ferrous  oxalate 
development,  unless  the  reserve  developer  be  resorted  to.  The  defect  may  lie  in  the 
emulsion  itself  being  insensitive,  or  it  may  contain  too  much  soluble  bromide,  and  have 
been  very  indifferently  washed.  Such  an  emulsion  requires  a  powerful  alkaline  de- 
veloper, as  ferrous  oxalate  is  of  very  little  use  under  the  circumstances. 

The  Negative  is  Full  of  Detail,  but  too  Dense. — When  the  developer  has  been  allowed  to 


NEGATIVE-MAKING  —  DRY.  401 

cast  that  our  art  is  "easy" — that  "anyone  can  make  good  photographs." 
Therefore  when  failures  and  faults  lift  themselves  up  in  the  way,  a  good  deal 

act  on  the  plate  too  long,  the  density  may  be  reduced  by  soaking  the  plate,  after  fixing, 
in  a  weak  solution  of  perchloride  of  iron  (1-50  to  1-100).  When  the  density  is  suffi- 
ciently reduced,  the  plate  should  be  placed  in  the  fixing  solution,  and,  if  necessary,  the 
operation  can  be  repeated.  The  1  per  cent,  or  2  per  cent,  solution  of  potassium  cyanide 
is  effective,  but  is  apt  to  attack  the  half-tones,  and  increase  the  contrast.  Burgess 
recommends  soaking  the  negative,  after  fixing,  in  a  (1-60)  solution  of  chloride  of  gold, 
and,  after  the  yellow  color  which  it  gives  to  the  negative  has  reached  through  to  the 
back  of  the  plate,  the  latter  should  be  again  placed  in  the  fixing  solution  to  dissolve  off 
the  chloride  of  silver  formed  on  the  film. 

The  Negative  Exhibits  a  Coarse  Grain. — This  is  due  to  defects  in  preparing  the  emul- 
sion. The  solution  of  silver  has  been  too  concentrated,  the  emulsion  has  been  cooked 
too  long,  too  much  ammonia  has  been  added,  or  the  proportion  of  silver  in  the  emulsion 
has  been  too  large.  It  is  impossible  to  remedy  this  defect. 

The  High  Lights  are  surrounded  by  a  Halo. — This  is  sometimes  due  to  a  defect  in  the 
lens,  but  it  generally  occurs  from  reflection  of  light  from  the  back  of  the  plate.  This 
defect  is  not  apparent  when  the  films  are  thick,  or  when  the  plates  are  backed.  The 
proposal  to  color  the  emulsion  itself  is  impracticable,  as  such  a  process  is  found  to  reduce 
the  sensitiveness  of  the  emulsion.  There  is  a  reflection  from  the  film  itself,  too,  which 
often  causes  this  halo  round  the  high  lights.  Plates  which  have  a  matt  surface,  or  which 
contain  iodide,  are  not  liable  to  this  defect. 

The  Negative  becomes  Reversed  during  Development. — This  phenomenon  or  (so-called) 
solarization  occurs  principally  when  the  exposure  has  been  abnormally  long.  Plates 
liable  to  this  defect  should  be  developed  for  as  short  a  time  as  possible,  and  with  a  weak 
developer.  Sometimes  this  effect  of  solarization  is  apparent  when  only  an  ordinary  ex- 
posure has  been  given.  If  this  is  so,  probably  actinic  light  has  reached  the  plate  before 
exposure.  Too  much  hyposulphite  in  the  developer  also  reverses  the  image. 

Frilling  and  expansion  of  the  film,  etc.,  generally  attend  the  use  of  too  soft  a  sample  of 
gelatine.  It  may  also  be  due  to  incipient  decomposition  of  the  gelatine,  owing  to  too 
long  cooking,  or  other  causes,  or  the  use  of  too  thick  films.  The  emulsion  may  also 
contain  gum-arabic,  or  the  plates  may  have  dried  irregularly,  the  part  that  takes  longest 
to  dry  being  the  first  to  frill. 

6.  The  same  thing  occurs  sometimes  during  development  with  pyrogallic  acid  when 
too  much  alkali  has  been  employed. 

c.  When  the  developer  or  the  wash-water  is  too  warm. 

d.  When  too  strong  a  solution  of  hyposulphite  of  soda  has  been  used. 

e.  When  plates  have  been  treated  with  dilute  acid  solutions. 

It  is  often  useful  to  coat  the  plates  with  a  substratum  of  water-glass  (1 :  200),  or  else 
give  an  edging  with  a  solution  of  rubber.  The  best  cure,  however,  is  undoubtedly  to 
soak  the  plates  either  before  or  else  after  development  in  a  3  or  5  per  cent,  solution  of 
alum  or  chrome  alum  for  a  few  minutes.  Williams  recommends  a  mixture  of:  Tannin, 
18  parts;  alum,  18;  glycerine,  48;  and  water,  380. 

26 


402        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

of  surprise  and  disappointment  follows.     This  should  not  be  so,  because  it  is 
not  reasonable  to  expect  photography  to  run  any  smoother  than  other  pursuits 

Chardon  recommends  soaking  the  plates  in  alcohol  before  development,  and  in  a  50 
per  cent,  solution  of  alum  between  development  and  fixing.  It  is  often  advisable,  in 
developing  plates  which  have  a  tendency  to  frill,  to  use  double  the  ordinary  proportion 
of  pyrogallic  acid,  and  make  up  the  solution  half  with  water  and  half  with  alcohol. 

Chrome  alum  may  also  be  added  to  the  developer  in  the  proportion  of  J  to  1£  grammes 
to  every  500  c.  c.,  or  the  addition  of  1  to  3  per  cent,  alum  to  the  fixing  solution  may  also 
be  recommended. 

Abney  advises  that  plates  liable  to  frill  should  be  coated  before  development  with 
plain  collodion,  and  then  be  washed  until  the  greasy  lines  disappear,  and  the  water  flows 
off  the  plates  evenly.  The  development  may  then  be  proceeded  with  without  any  fear 
of  frilling. 

The  Negative  takes  a  Long  Time  to  Fix. — This  occurs  equally  when  the  solution  is  too 
dilute  or  too  concentrated.  The  strength  of  the  fixing  solution  should  be  regulated  to 
about  1  to  5. 

Intensification  with  Silver  Nitrate. — Red  fog  is  very  apt  to  make  its  appearance  during 
the  process  if  the  intensifier  is  not  kept  continually  in  motion,  if  it  contains  too  little 
acid  as  a  restrainer,  or  when  the  last  trace  of  hyposulphite  of  soda  has  not  been  removed 
from  the  film.  Red  fog  can  often  be  got  rid  of  by  treating  the  plates  with  a  1  or  2  per 
cent,  solution  of  hydrochloric  acid,  or  by  soaking  in  a  strong  solution  of  common  salt. 
If  citric  acid  be  used  in  excess,  it  has  a  solvent  action  on  the  film. 

Failures  during  Mercury  Intensification. — The  hyposulphite  of  soda  should  be  thor- 
oughly washed  off  in  all  forms  of  mercury  intensification  with  the  exception  of  Edwards's 
method,  otherwise  the  treatment  with  mercury  will  give  a  brown  stain. 

b.  The  same  thing  occurs  if  the  bichloride  of  mercury  is  not  thoroughly  washed  off 
before  the  ammonium  sulphide  or  hyposulphite  of  soda  is  flowed  over  the  film. 

Failures  in  Intensifying  with  Uranium. — If  the  fixing  solution  is  not  thoroughly  washed 
off,  the  film  turns  brownish-red  on  the  application  of  solutions  of  uranium  salts.  Any 
traces  of  ferrous  oxalate  left  in  the  film  gives  rise  to  a  bluish  color. 

The  Negative  becomes  Darker  after  Fixing — This  defect  may  generally  be  traced  to 
intensification.  It  occurs  when  plates  have  been  intensified  with  mercury  or  with  silver, 
and  in  the  latter  case,  especially  if  the  precaution  has  been  omitted  of  removing  all  free 
silver  by  replacing  the  negatives  in  the  fixing  solution.  The  only  recourse  left  is  to 
remove  the  varnish  and  attempt  to  clear  the  plate. 

c.  Negatives  which  have  been  printed  from  before  varnishing,  often  turn  red,  owing 
to  the  silver  in  the  paper  combining  with  the  gelatine  to  form  red  stains.    The  stains 
can  be  removed  with  dilute  potassium  cyanide. 

Negatives  have  an  opalescent  appearance  when  they  have  not  been  thoroughly  dry 
before  varnishing. 

The  Plates  Fade  after  Varnishing. — This  is  due  to  intensification,  and  is  often  met  with 
in  plates  which  have  been  intensified  with  England's  or  Edwards's  methods.  The  only 
remedy  is  to  remove  the  varnish,  and  try  some  other  method  of  intensification. — DR.  J. 
M.  EDER. 


NEGATIVE-MAKING  —  DRY.  403 

and  recreations  do.     And  I  do  not  feel  sure  that  our  art  would  hold  the 
fascination  which  it  does  for  such  myriads.     Now,  if  it  was  all  "  smooth  sail- 

Flatness  of  Image  is  usually  due  to  overexposure  and  development  with  the  alkaline 
developer;  the  use  of  ferrous  oxalate  mitigates  the  evil;  while,  if  iodide  be  in  the  film, 
we  have  never  found  any  great  lack  of  density  to  arise.  Feebleness  of  the  image  is  also 
often  caused  by  too  thin  a  coating  of  emulsion.  In  our  own  experience  a  thick  film  is 
a  desideratum,  giving  all  the  necessary  density  to  the  image  with  facility.  Remember 
that,  when  a  vigorous  image  is  required,  it  is  most  readily  obtained  by.  using  a  freshly 
prepared  and  strong  ferrous  oxalate  solution. 

Too  great  Density  of  Image  is  sometimes  met  with,  and  can  be  remedied  by  applying 
ferric  chloride  to  the  film,  and  then  subsequently  immersing  in  the  hyposulphite  of 
soda  fixing  bath. 

The  formula  recommended  is;  Ferric  chloride,  one  drachm;  water,  four  ounces.  This 
is  flowed  over  the  plate  a  short  time,  and  then,  after  washing,  the  plate  is  immersed  in 
the  fixing  bath.  The  solution  acts  very  vigorously,  and  should  be  diluted  if  only  a  small 
reduction  is  required.  Local  reduction  may  be  effected  by  using  a  paint  brush  charged 
with  this  solution  on  the  moistened  film.  This  practice  is  not,  however,  much  to  be 
commended,  as  it  is  rather  working  in  the  dark. 

Density  may  also  be  diminished  by  the  use  of  a  strong  solution  of  cyanide.  Local 
reduction  may  be  given  by  moistening  the  parts  required  to  be  reduced  with  water  by  a 
paint  brush  and  then  applying  the  cyanide  in  the  same  manner.  The  reduction  can  be 
seen  progressing. 

There  are  a  variety  of  formulae  for  reducing  negatives.  Perhaps  the  best  is  eau  de 
javelle,  which  can  be  obtained  of  all  chemists,  but  which  is  made  as  follows:  Dry  chlo- 
ride of  lime,  2  ounces;  carbonate  of  potash,  4  ounces;  water,  40  ounces.  The  lime  is 
mixed  with  30  ounces  of  the  water  and  the  carbonate  dissolved  in  the  other  10  ounces. 
The  solutions  are  mixed,  boiled,  and  filtered.  The  filtered  solution  should  be  diluted, 
and  the  plate  immersed  in  it  till  reduction  takes  place.  The  plate  should  be  fixed  and 
again  washed. 

Yellow  Stains. — Usually  a  yellowish  veil  appears  to  dim  the  brightness  of  the  shadows 
when  the  development  has  been  effected  by  the  alkaline  developer.  This  may  be 
removed,  if  thought  requisite,  by  the  application  of  one  or  two  drops  of  hydrochloric 
acid  to  an  ounce  of  water  and  floating  it  over  the  surface  of  the  plate.  The  film  must 
be  washed  almost  immediately,  as  the  acid  is  apt  to  cause  frilling. 

Another  formula,  due  to  Mr.  J.  Cowell,  is  to  immerse  the  plate  in  alum,  2  ounces ; 
citric  acid,  1  ounce;  water,  10  ounces. 

Another  formula  is:  Saturated  solution  of  alum,  20  ounces;  hydrochloric  acid,  £  ounce. 
The  negative  should  be  well  washed  in  all  cases  after  the  application  of  either  of  them. 

Too  Granular  an  Emulsion  is  usually  due  to  bad  mixing  of  the  soluble  bromide  and 
the  silver  nitrate,  but  it  may  also  be  caused  by  overboiling,  and  also  by  too  small  a  quan- 
tity of  gelatine  in  the  boiling  operation.  Digesting  too  long  with  ammonia,  as  in  Van 
Monckhoven's  process,  has  the  same  effect.  There  is  no  cure  for  this  evil. 

Opaque  /Spots  on  a  plate  are  almost  invariably  due  to  dust  settling  on  the  film  when 
drying;  they  also  may  be  due  to  imperfect  filtering  of  the  emulsion. 


404        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

ing,"  we  should  then  lose  our  feeling  in  it — our  respect  for  it  if  it  was  "  easy." 
One  of  the  chief  attractions  attending  it  consists  in  the  knowledge  that  one 
may  fail  awfully  with  it  if  one  is  not  carefully  and  constantly  on  the  alert. 

Semi-transparent  Spots  on  the  plate  before  development  are  generally  due  to  (1)  excres- 
cences on  the  glass  plate,  or  (2)  to  the  use  of  gelatine  containing  grease. 

Certain  gelatines  are  apt  to  contain  grease,  and  that  so  intimately  that  soaking  in 
ether  or  washing  with  ammonia  will  not  eliminate  it.  A  specific  is  as  follows :  We  will 
suppose  that  80  grains  of  Coignet's  gelatine  are  required :  90  grains  are  weighed  out, 
soaked  in  water,  drained,  and  melted.  The  liquid  is  then  very  slowly  poured,  almost 
drop  by  drop,  into  methylated  spirit,  free  from  resin,  where  it  is  precipitated  in  shreds 
of  a  white  pasty  character;  after  it  is  all  precipitated,  the  spirit  is  poured  off  and  a 
slight  rinse  with  fresh  spirit  given,  and  then  it  is  covered  with  water,  in  which  it  should 
remain  till  the  whiteness  disappears.  The  water  should  then  be  changed  and  the  gela- 
tine drained  and  redissolved ;  about  10  grains  out  of  the  90  seem  to  be  dissolved  in  the 
mixture  of  alcohol  and  water.  Emulsions  made  with  this  gelatine  will  be  markedly 
free  from  grease  spots.  The  same  method  may  be  adopted  for  large  quantities  of  gela- 
tine, omitting  the  final  wash  with  water  and  leaving  it  to  dry  spontaneously.  This  is 
best  done  on  glazed  dishes.  The  gelatine  can  be  broken  up,  weighed,  and  used  in  the 
usual  manner. 

Dull  Spots  on  the  Negative  are  also  due  to  the  use  of  gelatine  which  contains  greasy  matter. 

Want  of  Density  in  a  negative  may  be  caused  by  over-exposure,  but  it  more  often 
arises  from  the  emulsion  itself.  A  rapid  emulsion  will  always  give  a  feebler  image  than 
a  slow  emulsion,  although  to  form  the  image  the  same  amount  of 'silver  may  be  reduced. 
This  shows  that  the  silver  is  in  such  a  state  of  aggregation  that  it  does  not  possess  what 
may  be  called  covering  powers.  We  have  found  that  the  addition  of  a  chloride  emul- 
sion materially  aids  the  production  of  density.  If  one-fifth  of  an  emulsion  be  added  to 
an  emulsion  lacking  in  density  giving  qualities,  it  will  be  secured  without  detriment  to 
the  sensitiveness.  The  range  of  sensitiveness  will  be  slightly  altered.  A  hard  gelatine 
is  also  conducive  to  feeble  images.  If  prepared  plates  give  feeble  images,  resort  must 
be  had  to  intensifying. — CAPT.  ABNEY. 

The  round  and  matt  spots,  which  are  already  visible  on  the  plate  before  development 
(they  form  small  wells  or  depressions)  give  darker  spots  in  the  negative  that  has  been 
developed  and  fixed.  Unfortunately,  these  defects  are  often  met  with,  and  more  fre- 
quently when  pure  gelatine  has  been  used,  instead  of  soft  gelatine,  which  sets  more 
slowly.  These  spots  arise  in  most  cases  from  a  want  of  proportion  between  the  bromide 
of  silver,  the  gelatine,  and  the  water.  The  greater  the  proportion  of  gelatine,  compared 
to  that  of  the  bromide  of  silver,  the  less  often  they  are  found;  and,  on  the  other  hand, 
they  are  more  easily  produced  when  the  emulsion  contains  a  greater  quantity  of  water. 
It  is  difficult  to  remedy  this  defect;  the  best  thing  to  do  is  to  add  to  the  emulsion  a  solu- 
tion of  gelatine  (one  to  six).  Dust,  and  the  small  filaments  which  fall  into  the  emulsion 
which  has  not  entirely  set,  give  rise  to  spots  which  present  some  analogy  to  those  men- 
tioned above,  but  they  are  not  entirely  round.  Seen  through  the  microscope,  they  show 
the  nucleus  of  the  spot  formed  by  the  grain  of  dust. 


NEGATIVE- MAKING  —  DRY. 


405 


FIG.  330. 


FIG.  331. 


The  navigator  of  the  broad  and  turbulent  Mississippi  finds  a  peculiar  charm 
in  piloting  his  way  along  it,  because  he  knows  that,  although  snags  and 

The  black  spots,  coming  from  contact  with  the  fingers,  are  due  to  the  plate  having  been 
touched,  before  or  after  development,  by  fingers  to  which  has  adhered  a  trace  of  hypo-, 
sulphite. 

Waves,  striae,  and  the  clouds  (Fig.  330)  are,  for  the  manufacturer  of  emulsion,  a  veri- 
table calamity.  They  may  arise  from  different  causes.  For  example,  if  the  emulsion  is 
spread  over  plates  with  a  cold  glass  rod, 
or  by  means  of  a  brush  upon  which 
there  remains  a  portion  of  half  con- 
gealed emulsion  (this  is  rarely  the  case 
with  hand-made  plates),  or  when  some 
portions  of  the  emulsion  are  badly 
mixed  or  badly  spread.  (Fig.  331.) 

When  there  is  a  great  difference  of 
temperature  between  the  plates  and  the 
emulsion,  these  waves  are  very  likely 
to  be  produced ;  as  is  the  case,  also,  if 

hard  gelatine  has  been  used,  which  sets  very  rapidly;  whilst,  with  soft  gelatine,  they  form 
with  greater  difficulty.  The  emulsion  prepared  by  ebullition  is  less  subject  to  this  defect 
than  the  emulsion  containing  ammoniacal  oxide  of  silver.  But  almost  always  the  cause 
is  due  to  a  defective  proportion  between  the  bromide  of  silver,  the  gelatine,  and  the  water. 
When  the  gelatine  and  the  bromide  are  in  equal  proportions,  and  there  is  but  little  water, 
these  waves  are  almost  always  produced ;  it  is  the  contrary,  when  the  proportion  of  gela- 
tine is  twice  as  great,  and  there  is  a  sufficient  quantity  of  water,  and  especially  when  a 
definite  proportion  of  gelatine  has  been  added.  The  proportion  indicated  by  the  author 
is  the  right  one.  Moreover,  the  precaution  may  be  taken  of  heating  the  emulsion  for 
ten  minutes  before  using  it,  so  as  to  obtain  a  perfect 
mixture. 

Cloudy  spots  are  produced  if,  when  the  ammonia  is 
poured  into  the  pyro  developer,  care  has  not  been  taken 
to  make  the  mixture  in  a  separ- 
ate dish.  Wherever  the  ammo- 
nia has  been  allowed  to  touch 
bright  spots  are  produced  in 
reflected  light,  which  are  but 
slightly  visible  in  transmitted 
light. 

The  plate  presents  the  ap- 
pearance of  a  honey  comb,  even 
before  development  (Figs.  332, 
333).     This  comes  from  the  emulsion  containing  too  much  alcohol,  or  from  too  much 
alcohol  having  been  added,  or  from  the  emulsion  having  been  kept  too  long  under  the 
alcohol. 


FIG.  333. 


FIG.  332. 


406        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

sawyers  abound,  he  possesses  the  skill  to  dodge  them,  and  that  he  is  going  to 
do  it  almost  every  time.     A. kindred  pleasure  awaits  the  patient  and  loving 

Failures  in  using  Mercury  Salts. — In  all  these  strengthening  processes,  with  the  excep- 
tion of  that  of  Edwards's  here  are  the  causes  of  these  failures : 

a.  Traces  of  sodic  hyposulphite,  which  give  a  brown  color  to  the  salts  of  mercury 
(precipitation  of  the  sulphuret  of  mercury).     The  plates  have  a  strong  veil.    Remedy: 
Complete  elimination  of  the  hyposulphite  by  washing,  before  and  after  the  mercury 
treatment.     It  is  difficult  to  remove  spots  on  the  negative.     According  to  Kuntzmiiller, 
success  is  more  easily  obtained  by  using  a  solution  of  chloride  of  gold. 

b.  If  the  last  traces  of  the  solution  of  mercury  are  not  completely  removed  by  washing 
before  treating  the  negative  with  ammonia  or  hyposulphite,  a  very  dark  and  intense  veil 
is  formed. 

c.  A  gray  veil  is  almost  always  formed  when  the  negative  was  already  veiled  before 
strengthening. 

d.  When  the  washing  has  been  insufficient  after  the  chloride  of  mercury  bath,  and 
before  treating  with  ammonia  or  cyanide,  spots  are  met  with  of  the  shape  shown  in 
Fig.  333.— LEON  VIDAL. 

Things  to  "Don't." — People  who  expect  to  use  cheap  lenses  and  the  sham  built  cheap 
outfits,  and  expect  to  make  beautiful  negatives  don't  succeed.  Reason  why:  Cheap 
lenses  are  one  of  the  curses  of  amateurs.  They  wont  penetrate,  define,  and  yet  give  a 
flat  field.  May  be  good  in  one  or  two,  but  never  in  the  three  absolute  requisites.  And 
the  cheap  "boxes"  have  no  swing  back  or  lifting  front,  and  when  you  must  tilt  the  box 
to  get  in  a  bit,  you  upset  all  the  rest. 

Changing  plates  once  a  week  and  developers  semi-occasionally  is  good  practice,  but  it 
is  bad  for  the  success.  Use  one  plate,  and  either  expose  the  plate  with  a  given  lens  and 
light  so  as  to  produce  a  fine  negative  with  a  given  strength  of  developer,  and  when  you 
have  learned  it,  then  change  time  of  exposure,  and  modify  your  developer,  but  don't 
undertake  to  do  it  all  at  once  if  you  expect  fine  prints 

Don't  use  anybody's  concentrated  developers ;  under  certain  circumstances  they  may 
do  fair  work,  but  under  all  the  varying  lights  and  times  of  exposure  to  which  the  amateur 
tramp  is  subject,  the  concentrated  developer  don't  give  fine  results. 

Don't  use  anybody's  double  guaranteed  developer  that  has  bromide  of  everything  except 
brains  in  it.  Whether  you  believe  it  or  not,  bromide  actually  calls  for  the  use  of  more 
pyro  and  we  are  all  using  more  than  too  much  pyro  now.  And  while  we  are  on  the 
subject  of  bromides,  allow  me  to  say  that  bromide  of  soda  is  worth  all  the  other  bromides 
when  soda  or  potash  is  in  the  developer,  and  bromide  of  ammonium  is  positively  not 
allowable  in  some  of  the  combinations  of  soda  and  potash.  Citrate  of  soda  is  an  elegant 
retarder,  but  all  hands  use  too  much,  as  a  rule.  Don't  underexpose ;  you  can  hold  in  a 
plate,  but  you  can't  force  one  any  more  than  get  blood  out  of  a  brick.  When  you  find 
the  image  coming  too  fast  don't  pour  in  bromide  to  increase  density,  but  put  in  a  lot  of 
water — filtered  water;  reduce  the  strength  of  the  developer;  keep  the  pan  moving  and 
you  will  see  when  the  retardation  shows  plainly,  then  keep  watch,  bring  it  up  to  density, 
and  don't  lean  on  bromide  so  much;  you  will  get  a  far  cleaner  negative,  finer  gradations, 
and  a  degree  of  harmony  that  bromide  will  not  give. 


NEGATIVE-MAKING  —  DRY.  407 

photographer.     The  long  list  of  obstacles  given  in  these  pages  is  not  intended 
to  frighten,  but  only  to  forewarn  that  you  may  be  forearmed. 

Don't  use  anybody's  solution  of  pyro.  Careful  experiment  has  demonstrated  the  fact 
that  pyro  decreases  in  energy  very  rapidly  after  a  very  few  weeks.  Many  a  negative  is 
spoiled  by  the  use  of  old  pyro  solution — two  months  old  and  older,  and  the  inveterate 
use  of  bromide.  Both  of  them  are  to  the  photographer  what  poor  paper  is  to  the 
artistic  printer. 

Don't  be  careless  or  slouchy  about  your  work.  When  the  light  is  let  upon  a  plate  it 
ought  to  give  a  beautiful  result ;  if  you  have  been  careless  in  focussing,  don't  curse  the 
plate  maker. 

Don't  use  alum  or  chrome  alum  in  your  hypo ;  keep  the  two  solutions  separate.  The 
alum  does  the  scavenger's  work  on  the  plate  after  development,  and  then  after  washing. 
The  hypo  does  its  work  clean,  clear,  quickly,  and  much  better  than  it  could  or  would  if 
the  alum  was  discharging  the  filth  into  the  hypo. 

Don't  use  an  old,  yellow,  or  filthy  solution  of  hypo ;  when  the  solution  becomes  dis- 
colored, throw  it  away.  Never  mind  if  some  slouch  has  said  he  did  use  it;  some  people 
like  to  eat  their  food  from  soiled  table  covers,  we  don't. 

Don't  imagine  you  are  so  much  smarter  than  the  other  fellow,  and  can  do  what  he 
couldn't.  You  may  sit  down  hard,  only  to  find  out  there  is  another  fool  in  town  (look 
in  the  glass). 

In  using  quick  plates  remember  that  more  cleanliness  is  necessary ;  more  care  in  filter- 
ing, more  accuracy  in  weighing  and  measuring,  more  care  in  the  light,  and  plate-holders, 
pans,  washing,  etc.,  for  they  are  so  much  more  sensitive  that  it  requires  more  sensible 
careful  manipulation. 

Don't  imagine  that  you  are  to  get  to  the  top  of  the  ladder  in  four  weeks,  photo- 
graphically. 

Don't  believe  all  you  hear,  but  do  as  the  old  goose  did  when  he  stood  on  one  leg  to  see 
how  long  he  could  do  so — ''try  it  and  see. 

Don't  change  plate  or  formula  everv  time  you  hear  a  big  story ;  shut  one  eye  and  think 
it  over,  sleep  on  it,  and  then  don't 

Don't  be  economical ;  get  the  best,  and  then  learn  how  to  use  it ;  keep  cool ;  read  all 
you  can  get  hold  of,  and  then  sift  it,  and  if  you  get  burnt  semi-occasionally,  you  will 
learn  a  lot,  and  what  you  know  be  sure  of. 

Don't  expect  to  get  rich  the  first  year. 

Don't  swear  at  ill  luck ;  sit  down  and  think  it  all  over.  You  may  not  see  the  rascal, 
but  you  know  him. 

Don't  believe  any  of  this  if  you  don't  want  to. 

Don't  believe  that  any  developer  is  the  best  and  only  scientific  developer,  unless  you 
want  to ;  keep  on  spoiling  good  plates,  and  swearing.  When  you  get  sensible,  get  a 
formula;  prepare  it;  use  it  with  care;  mix  in  a  little  brains;  and  you  will  have  one  of 
the  best  things  I've  found  in  four  years.  And  lastly,  dear  reader,  don't  write  me  lots  of 
letters  asking  why  and  wherefore  and  forget  that  postage  stamps  cost  me  cash,  while 
courtesy  is  valued  highly.— THOS.  PRAY,  JR. 


408         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

174.  Once  a  satisfactory  negative  has  been  obtained,  every  precaution  will 
be  taken  to  protect  it — from  the  heartless,  unsympathetic  handling  of  the 

174.  If  anyone  will  varnish  a  gelatine  negative  simply  with  the  usual  negative  var- 
nishes— upon  which  retouching  can  be  done  without  grinding  the  surface — he  can  make 
all  his  retouching  useless  by  simply  allowing  a  few  drops  of  water  to  fall  on  the  surface, 
or  by  allowing  his  hand  to  rest  on  it  while  perspiring  or  moist.  The  effect  is  at  once 
seen  in  semi-opaque  spots,  which  show  badly  in  printing,  and  can  only  be  got  rid  of  by 
revarnishing,  thus  making  the  labor  in  vain.  Retouching  direct  on  the  surface  of  the 
gelatine,  and  then  varnishing,  would  obviate  this,  but  most  retouchers  do  not  find  it  a 
desirable  surface  by  itself. 

But  there  is  another  aspect  to  this  case.  A  surface  so  easily  affected  by  moisture  is 
not  safe  against  other  deleterious  causes.  The  reason  for  this  is  obvious.  The  varnish 
mostly  used  is  composed  of  gum  sandarac,  alcohol,  and  sufficient  gum  turpentine  to  give 
it  a  soft,  yielding  surface,  causing  the  pencil  to  take  it  readily.  From  considerable 
experience  with  varnishes,  I  find  this  one  of  the  best  for  retouching  purposes,  and  the 
one  most  generally  in  use.  The  weak  spot  in  it  for  gelatine  plates  is  the  gum  turpentine. 
It  may  be  asked,  Why  not  use  shellac  entirely?  True,  this  varnish  does  not  allow 
moisture  to  penetrate  direct,  if  thick  enough,  but  it  is  the  poorest  of  all  varnishes  for 
practical  use,  because  the  surface  is  so  hard  as  to  require  grinding — a  most  pernicious 
practice,  making  collodion  plates  hard  and  slow  enough  in  printing,  but  still  worse  for  a 
gelatine 'negative  of  good  strength.  A  further  objection  is  that  from  its  filmy,  contractile 
nature,  should  the  negative  ever  be  exposed  to  a  continued  damp  atmosphere,  such  as  in 
basements  or  cellars,  it  would  cause  them  to  peel  off,  as  in  stripping  plates.  I  have  often 
witnessed  this  effect  on  collodion  plates;  and  I  have  also  noticed  that  negative  films 
varnished  with  shellac  are  the  soonest  eaten  off  in  the  acid  dish,  while  those  varnished 
with  sandarac  hold  on  much  longer.  In  fact,  shellac  and  mastic  varnishes  have  the  least 
stability  of  any. 

Now  to  the  remedy,  and  a  perfect  safeguard  for  gelatine  negatives.  I  have  found  that 
the  original  method  of  first  coating  the  plate  with  plain  collodion,  and  then  varnishing, 
to  be  a  perfect  and  reliable  protection.  We  use  a  collodion  containing  six  grains  to  the 
ounce  of  gun  cotton,  and  about  thirty  drops  of  castor-oil  to  the  pound.  Our  varnish  is 
composed  of  two  ounces  of  sandarac,  half  ounce  of  the  lightest  orange  lac  to  one  pint  of 
alcohol ;  to  which  one  drachm  of  castor-oil  is  added,  instead  of  using  gum  turpentine,  to 
give  a  tooth  to  the  pencil.  Bleached  lac  may  be  used,  but  it  does  not  come  regular  in 
quality,  and  if  very  old  is  insoluble.  The  color  given  by  the  amount  of  orange  lac  used 
is  not  objectionable,  but  those  who  object  could  use  sandarac  alone,  though  it  does  not 
dry  as  nicely  or  with  as  little  heat  as  when  a  little  lac  is  used  with  it.  It  will  be  seen 
that  we  here  have  a  varnish  on  a  film  of  collodion  covering  the  gelatine ;  and  I  have 
found  it  to  stand  immersion  in  water  a  long  time  without  moisture  being  absorbed  by  it. 
I  would  warn  others,  however,  that  no  amount  of  protection  can  make  a  plate  that  has 
been  treated  with  mercurial  salts  safe  against  deterioration;  the  most  of  such  will  go. 
I  have  found  several  negatives  made  in  1881,  developed  with  oxalate  and  thoroughly 
washed  free  from  hypo,  that  have  become  much  weaker.  They  were  not  intensified, 


NEGATIVE-MAKING  —  DRY.  409 

printer.  Varnish  is  the  best  preservative,  and  the  method  of  application  is 
very  similar  to  what  has  been  offered  for  the  "  wet "  negative. 

175.  By  far  the  most  learned  treatise  published  on  bromo-gelatine  work  is 

were  protected  with  varnish,  and  kept  in  a  dry  place.  The  later  ones  have  apparently 
not  been  affected  as  yet,  and  it  is  also  somewhat  premature  to  decide  as  to  the  permanence 
of  gelatine  negatives. — D.  BACHRACH,  JR. 

175.  PRACTICAL  NOTES.  The  precipitation  of  an  unwashed  emulsion  by  alcohol  has  been 
recommended  by  Wratten  and  Waiuright,  as  well  as  -by  Obernetter,  on  the  ground  that 
while  the  gelatine  itself  is  insoluble  in  alcohol,  the  bi-products  enter  into  solution. 
The  process  is,  no  doubt,  much  more  rapid  than  that  of  long-continued  washing ;  but  it 
must  be  borne  in  mind  that  potassium  bromide  and  potassium  nitrate  are  both  very  solu- 
ble in  water,  and  only  slightly  so  in  alcohol.  The  ammonium  salts  are  far  more  soluble. 
There  is  another  inconvenience  attaching  to  the  process,  in  the  fact  that  gelatine  which 
has  been  precipitated  with  alcohol  takes  a  long  time  to  dissolve  in  water. 

Drying  of  Gelatine  Plates. — There  is  danger  of  fog  if  plates  take  too  long  a  time  to  dry. 
From  twelve  to  eighteen  hours  is  about  the  correct  time ;  if  this  period  is  exceeded,  a 
few  drops  of  carbolic  acid  may  be  sprinkled  over  the  floor  of  the  drying-room.  The 
easiest  and  the  best  way  to  dry  plates  is  to  stand  them  on  racks  in  an  ordinary  light-tight 
room.  If  there  is  such  moisture  in  the  air,  calcium  chloride  or  sulphuric  acid  may  be 
employed  to  absorb  it.  If  a  drying-cupboard  is  used,  the  temperature  should  be  about 
27°  C.  to  30°  C. 

Drying  Plates  by  means  of  Alcohol. — It  has  often  been  recommended,  as  a  means  of 
hastening  the  drying,  to  soak  the  plates  in  alcohol  for  a  few  minutes,  after  which,  if  stood 
on  edge,  they  will  dry  in  an  hour  or  two.  This  method  is  good  enough  for  drying  test- 
plates  ;  but  it  is  not  suitable  for  general  employment.  The  alcohol  soon  loses  its  power 
of  absorbing  water,  and  plates  which  have  been  dried  in  this  manner  are  liable  to  spots. 

Alcoholic  Solutions  of  Gelatine  or  Gelatine  Emulsion. — In  May,  1880,  I  observed  that 
gelatine  warmed  with  nitric  acid  was  highly  soluble  in  strong  alcohol ;  but,  as  it  also 
becomes  soluble  in  water,  it  is  of  no  use  for  preparing  plates.  According  to  Herschel, 
alcohol  to  which  two  per  cent,  of  aqua  regia  has  been  added  will  dissolve  under  the 
action  of  moderate  heat  any  quantity  of  gelatine.  The  film  is  insoluble  in  water,  and 
takes  about  twice  as  long  to  dry  as  a  collodion  emulsion.  Ether  and  chloroform  have  the 
same  solvent  action.  The  use  of  aqua  regia  lowers  the  sensitiveness  of  the  emulsion 
considerably.  According  to  Vogel,  gelatine  dissolves  in  organic  acids  without  precipi- 
tating. If  a  few  drops  of  acetic  acid  be  added  to  an  ordinary  gelatine  emulsion,  the 
latter  will  be  found  to  melt  more  readily,  and  to  set  with  greater  difficulty.  The  addition 
of  a  small  quantity  of  acetic  acid  tends  to  prevent  the  recurrence  of  small  pits  in  the 
film,  to  which  a  gelatine  that  sets  too  rapidly  is  liable.  His  new  emulsion  consists  of  a 
dry  gelatine  emulsion  and  pyroxyline  dissolved  in  alcohol  and  acetic  acid.  An  emulsion 
prepared  in  this  way  retains  its  normal  power  of  setting,  and  a  10  per  cent,  aqueous  solu- 
tion of  either  oxalic,  boracic,  or  succinic  acid  will  readily  dissolve  under  heat  half  its 
weight  of  gelatine,  and  the  solutions  admit  of  dilution  with  three  times  their  volume  of 
alcohol.  An  emulsion  dissolved  in  double  its  bulk  of  acidulated  water,  to  which  three 


410        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Modern  Dry  Plates  or  Emulsion  Photography,  by  Dr.  J.  M.  Eder,  my  distin- 
guished colleague  of  Vienna,  and  translated  by  a  lamented  friend,  H.  Baden 

volumes  of  absolute  alcohol  are  added,  can  be  poured  over  plates  like  collodion,  and  dries 
in  an  hour,  giving  the  same  sensitiveness  and  brilliancy  as  an  emulsion  dissolved  in 
water. 

Konarzewski  prepares  a  collodio-gelatine  emulsion  by  dissolving  1  gramme  of  pyroxylin 
in  50  c.  c.  alcohol  at  36°,  and  50  c.  c.  acetic  acid,  and  adding  10  grammes  of  dry  gelatine- 
bromide  emulsion ;  the  whole  being  dissolved  in  the  water  bath.  Such  an  emulsion  can 
be  poured  over  the  plate  like  collodion,  and  dries  much  more  rapidly  than  an  ordinary 
aqueous  emulsion.  If  the  plates  exhibit  any  tendency  to  frill  during  development,  a 
substratum  may  be  used  previous  to  coating.  Schlicht  prepares  an  alcoholic  solution  of 
gelatine  in  the  following  way :  He  precipitates  an  aqueous  gelatine  emulsion  with  alcohol, 
and,  when  dry,  he  adds  1  part  of  the  emulsion  to  1  part  acetic  acid,  allows  it  to  stand  for 
an  hour,  and  then  warms  it  over  the  water  bath,  when  solution  ensues  in  about  five 
minutes.  One  part  of  a  normal  collodion  and  acetic  acid  (1  to  4)  is  added  gradually  with 
constant  stirring,  the  bottle  being  kept  warm  during  the  addition.  The  emulsion  may 
then  be  diluted  with  f  part  of  a  mixture  of  alcohol  and  acetic  acid  (4  to  1)  and  filtered. 
It  is  a  curious  fact  that  such  alcoholic  gelatine  emulsions  are  not  so  easily  spoilt  by  an 
excess  of  silver  nitrate  as  aqueous  solutions.  Such  an  emulsion  may  be  prepared  with 
excess  of  silver  without  exhibiting  any  signs  of  red  fog  if  the  excess  of  silver  is  removed 
by  means  of  sodium  chloride. 

Wilde  informs  me  that  gelatine  swelled  in  water  is  soluble  in  alcohol  to  which  two  or 
three  times  its  bulk  of  acetic  acid,  neutralized  with  ammonia,  is  added.  Such  an  emul- 
sion, thinned  with  alcohol,  gives  a  clear  picture,  and  retains  its  power  of  setting  for  a 
considerable  time. 

On  the  Keeping  Qualities  of  Gelatine  Plates. — Camps  had  a  good  opportunity  of  testing 
this  during  the  sea  voyages  that  he  undertook.  He  found  that  they  remained  unaffected 
by  the  severest  changes.  The  preparation  of  gelatine  emulsion  is  extremely  difficult 
during  the  summer  months,  and  many  firms  discontinue  supplying  plates  during  the 
summer  time  in  consequence. 

The  Illumination  of  the  Dark-room. — Opinions  on  this  subject  are  very  conflicting. 
Some  photographers  contend  that  a  deep  ruby  light  is  necessary ;  others  are  in  the  habit 
of  using  orange  glass  only.  There  is  no  danger  in  the  latter  if  the  plates  are  protected 
from  its  direct  action  previous  to  development.  Ferrous  oxalate,  owing  to  its  deep  red 
color,  is  very  non-actinic,  and  a  plate  covered  with  a  good  body  of  solution  can  be 
brought  out  into  white  light  during  development.  Whaite  suggests  the  idea  of  coloring 
the  pyrogallic  developer  with  cochineal  for  the  same  purpose. 

Hyposulphite  of  Soda  in  the  Developer. — A  trace  of  hyposulphite  of  soda  during  develop- 
ment of  wet  collodion  plates  is  very  injurious.  In  the  case  of  dry  gelatine  plates  and 
pyrogallic  development  a  small  quantity  of  hyposulphite  of  soda  has  no  effect;  with  fer- 
rous oxalate  the  case  is  very  different.  Abney  observed  that  the  addition  of  a  few  drops 
of  a  solution  of  this  substance  to  ferrous  oxalate  brought  out  the  detail  rapidly,  and  he 
considers  that  its  use  admits  of  the  exposure  being  reduced  to  one-third.  If  the  plates 


NEGATIVE-MAKING  —  DRY.  411 

Pritchard.  It  is  published  by  Messrs.  E.  &  H.  T.  Anthony  &  Co.,  New 
York.  I  cannot  close  this  section  of  my  work  more  aptly  than  by  adding 
from  Dr.  Eder's  work  his  carefully  collated  practical  notes. 

consist  of  pure  bromide,  or  contain  chloride,  there  is  a  chance  of  a  reversal  of  the  image. 
I  may  mention  that  in  this  process  the  time  the  solution  should  be  allowed  to  act  after 
the  addition  of  the  hyposulphite  of  soda  depends  on  the  acidity  of  the  developer.  Ac- 
cording to  Abney,  it  is  best  to  add  the  hyposulphite  of  soda  as  soon  as  the  developer  has 
impregnated  the  film.  We  have  succeeded  very  well  with  plates  consisting  of  bromide 
of  silver  alone,  and  find  that  the  best  proportions  are  from  2  to  10  drops  of  a  1 : 100  solu- 
tion to  every  2  ounces  of  developer.  Larger  quantities  are  liable  to  give  reversed  images. 

Restoration  of  Old  Ferrous  Oxalate  Solution. — The  solution  containing  the  green  ferric 
crystals  should  be  warmed  in  an  earthenware  basin,  and  potassic  carbonate  added  until 
no  further  precipitate  is  given  after  filtration.  A  small  quantity  of  the  solution  may  be 
tested  now  and  then  for  the  purpose.  The  filtrate  contains  only  a  trace  of  iron,  and 
consists  for  the  most  part  of  pure  potassic  oxalate  containing  an  excess  of  potassic  car- 
bonate. The  solution  may  be  neutralized  with  oxalic'  acid,  and  a  further  addition  of 
potassium  oxalate  made  if  necessary.  If  there  is  much  potassium  bromide  present,  it 
can  be  removed  by  the  addition  to  every  100  c.  c.  of  solution  of  2  or  3  c.  c.  of  an  old  1 : 10 
sensitizing  bath.  The  solution  may  be  used  in  the  ordinary  way  after  having  been  fil- 
tered for  development.  Kohnkes'  suggestion  of  precipitating  the  iron  with  soda,  instead 
of  potash,  is  not  advisable,  as  the  solvent  action  of  sodium  carbonate  on  ferrous  oxalate 
is  much  less  than  that  of  the  potassium  or  ammonium  salts. 

Transparencies  with,  Gelatine  Plates. — These  can  readily  be  produced  by  exposing  gela- 
tine plates  under  a  negative  to  a  gas  flame,  and  developing  either  with  alkaline  pyrogallic 
or  ferrous  oxalate.  The  former  gives  a  brown,  and  the  latter  a  black  tone,  which  is  to  be 
preferred  for  this  class  of  work.  Transparencies  can  be  employed  for  the  reproduction 
of  negatives,  but  such  negatives  are  never  equal  in  delicacy  to  the  original.  A  method 
was  given  in  the  Photographic  News  of  producing  very  beautiful  transparencies  from 
emulsion  films  on  opal  glass,  which  can  be  afterwards  improved,  if  necessary,  by  retouch- 
ing with  a  pencil  or  crayon. 

Paper  coated  with  gelatine  emulsion  was  suggested  in  1874  by  Mawdsley,  and  can  be  pre- 
pared in  much  the  same  way  as  Warnerke's  sensitive  tissue.  No  doubt,  it  would  be 
useful  for  landscape  photography,  but  the  films  will,  of  course,  require  stripping  after 
fixing.  Ferran  and  Paul  recommend  the  following  method :  A  good  stout  description  of 
paper  is  moistened  and  stretched  on  a  board.  To  render  it  non-absorbent,  the  paper  is 
varnished  on  both  sides  with  a  solution  of  2  grammes  of  asphaltum  in  100  c.  c.  anhydrous 
benzine,  and  exposed  to  sunshine  for  an  hour  to  make  it  insoluble.  Either  one  of  the 
following  solutions  is  then  laid  on :  50  c.  c.  ether,  100  c.  c.  alcohol  at  42°,  1  or  2  grammes 
wax,  stearine,  or  paraffin ;  or  50  c.  c.  ether,  2  grammes  wax,  and  20  grammes  vaseline. 
After  the  ether  and  alcohol  have  evaporated,  the  emulsion  is  laid  on  with  the  addition  of 
a  small  quantity  of  glycerine  in  order  to  prevent  it  from  becoming  brittle  when  dry.  The 
negative,  after  being  developed  and  fixed,  is  coated  with  a  solution  containing  12  per 
cent,  gelatine  and  3  per  cent,  glycerine,  and  when  dry  the  film  can  easily  be  detached. 


412        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

And  yet,  with  all  these  things  before  us,  who  shall  say  that  the  end  of  the 
list  of  photographic  possibilities  has  come  ?  One  of  the  greatest  conquests  has 

Paper  sensitized  with  gelatine  emulsion  has  been  suggested  by  Swan.  Such  paper  is 
now  being  manufactured  by  a  number  of  parties,  and  admits  of  a  large  number  of  prints 
being  made  in  a  very  short  time.  The  paper  is  exposed  to  gaslight  under  a  negative, 
and  developed  with  ferrous  oxalate;  the  resulting  tone  being  a  cold  gray,  somewhat 
similar  to  platinotype. 

Employment  of  Gelatine  Emulsion  for  Reproduction  of  Drawings. — Gelatine  emulsion  is 
quite  as  well  adapted  for  this  class  of  work,  as  it  is  for  landscapes  or  portraiture.  The 
plates  should  be  well  exposed,  and  developed  with  ferrous  oxalate  containing  a  good  deal 
of  potassium  bromide  as  a  restrainer.  If  treated  in  this  way  they  rarely  require  any 
after- intensification,  but  in  case  such  a  proceeding  is  necessary,  mercury  is  the  best  agent 
for  the  purpose.  Ammonia  emulsion  is  most  suitable. 

Reversed  negatives  for  collotype  work  can  be  produced  by  exposing  with  the  film  side 
inwards,  the  necessary  correction  for  the  thickness  of  the  glass  being  made  after  focus- 
sing. In  developing  such  plates,  special  care  must  be  taken  about  the  cleanliness  of  the 
solutions  employed,  otherwise  the  surface  of  the  film  may  be  fogged  over  before  the  pic- 
ture which  is  on  the  inner  side  is  sufficiently  developed.  But  the  better  plan  is  to  use 
"  stripping  plates."  They  are  produced  by  J.  Carbutt,  of  Philadelphia,  and  are  used  by 
most  of  the  photo-mechanical  printers  in  America. 

Direct  Positives  in  the  Camera. — Negatives  on  collodion  emulsion  may  be  turned  into 
positives,  after  development,  by  soaking  in  concentrated  nitric  acid,  the  reduced  silver 
being  thus  dissolved  away ;  and  the  picture  then  consists  of  undissolved  bromide  of 
silver.  The  plate  should  then  be  briefly  exposed  to  light,  and  redeveloped,  or  treated 
with  ammonium  sulphide,  when  a  positive  image  will  result.  It  is  impossible  to  treat 
gelatine  plates  with  nitric  acid,  as  the  latter  attacks  the  film ;  but  we  found  that  it  was 
possible  to  employ  mercuric  nitrate  for  the  purpose,  without  danger  to  the  film.  If  a 
well- developed  gelatine  plate  be  treated  with  a  strong  solution  of  mercuric  nitrate,  a 
positive  image  quickly  appears.  The  plate  is  then  washed,  and  flooded  with  ammonium 
sulphide.  The  mercury  solution  should  not  be  too  concentrated,  otherwise  the  film 
shrinks,  and  gets  hard.  Brooks  gives  a  method  for  the  production  of  direct  positives  in 
the  camera.  A  bromide  or  chloro-bromide  plate  is  developed  to  the  full  extent  until  the 
picture  can  be  seen  at  the  back  of  the  plate.  It  is  then  laid  in  a  1  per  cent,  to  2  per 
cent,  solution  of  iodide  of  potassium  in  alcohol.  For  gelatine  plates,  it  is  preferable  to 
employ  a  solution  consisting  of  potassium  iodide  1  to  2  parts,  potassium  bromide  10  parts, 
and  water  100  parts.  The  original  image  disappears  entirely  in  this  solution,  and  a  pic- 
ture consisting  of  iodide  of  silver  on  bromide  of  silver  remains.  The  plate  is  then  washed 
and  treated  with  pyrogallic  or  ferrous  oxalate  developer,  which  attacks  the  bromide,  and 
leaves  the  iodide  of  silver  unaffected.  In  the  fixing  bath,  the  iodide  is  dissolved  away. 

Moonlight  Photographs. — Gelatine  plates,  owing  to  their  extreme  sensitiveness,  are 
available  for  this  purpose. 

Portraiture  by  Artificial  Light. — In  England,  France,  and  Belgium,  the  electric  as  well 
as  gaslight  is  made  use  of  in  various  studios  with  gelatine  plates.  The  results  are  highly 
satisfactory.  In  using  gas,  a  Wigham  or  Sugg's  burner  is  employed.  Mr.  Laws,  of 


NEGATIVE-MAKING  —  DRY.  413 

been  to  cause  gelatine  to  respond  in  sucli  an  orderly  manner,  as  detailed  by 
Dr.  Eder,  to  our  requirements.  It  was  like  the  "  Taming  of  the  Shrew  "  to 

Newcastle,  makes  use  of  a  large  burner  by  Wigham,  consisting  of  sixty-eight  jets,  giving 
a  total  intensity  of  light  of  1250  candles.  Reflectors  are  used  for  diffusing  the  light, 
and  a  shade  of  blue  glass  interposed  to  protect  the  sitter  from  the  heat.  The  use  of  this 
shield  increases  a  possible  exposure  of  seven  seconds  to  eight  seconds.  For  cartes,  Mr. 
Laws  gives  an  exposure  of  about  eight  seconds,  and  for  cabinet  portraits  twelve  to  fifteen. 
The  use  of  gas  is  well  worthy  of  attention  by  photographers,  owing  to  its  economy  as 
compared  with  the  electric  light. 

On  Blurring  in  Emulsion  Plates. — This  defect,  which  is  very  familiar  in  photographing 
interiors,  is  common  to  collodion  plates  as  well  as  thin  emulsion  films,  owing  to  their 
transparency,  and  the  consequent  reflection  of  light  from  the  back  of  the  plate.  The 
best  remedy  is  to  back  the  plate  with  some  dark,  non-actinic  substance.  Dyeing  the 
film  has  also  been  suggested ;  but  this  has  the  effect  of  reducing  the  sensitiveness  con- 
siderably. Plates  coated  with  an  emulsion  containing  iodide  of  silver  are  less  liable  to 
this  defect.  . 

Chloride  of  Silver  in  Emulsions. — An  addition  of  chloride  to  a  gelatine  emulsion  will 
not  be  injurious  as  long  as  there  is  an  excess  of  soluble  bromide  present.  Whilst  this 
lasts  the  chloride  of  silver,  as  fast  as  it  is  formed,  combines  with  the  potassium  bromide 
to  form  fresh  bromide  of  silver. 

The  Choice  of  a  Bromide  in  Preparation  of  Gelatine  Emulsion. — We  are  limited  practi- 
cally for  emulsion  work  to  the  bromides  of  either  potassium  or  ammonium,  as  if  the  salt 
of  a  heavier  metal,  such  as  zinc,  be  employed,  it  either  coagulates  the  gelatine,  or  affects 
its  setting  power.  Potassium  bromide,  owing  to  its  stability,  appears  more  suitable  than 
the  hygroscopic  ammonium  salt,  which  discolors  under  the  action  of  light.  The  potas- 
sium bromide  may  with  several  methods  be  neutral  or  slightly  acid,  but  not  alkaline. 
The  same  degree  of  sensitiveness  can  be  obtained  with  either  the  potassium  or  ammonium 
salt,  and  the  bi-products  have  no  injurious  effect  on  the  gelatine.  I  have  observed, 
however,  that  a  solution  of  ammonium  bromide,  when  heated,  is  readily  decomposed  into 
ammonia  and  hydrobromic  acid.  The  former,  at  a  temperature  of  30°  C.,  goes  off  in  the 
form  of  gas,  and  still  more  abundantly  at  a  temperature  of  100°  C. ;  hydrobromic  acid 
remains  behind,  giving  a  strong  acid  reaction,  which  may  be  very  injurious  to  the 
emulsion. 

Nearly  every  sample  of  bromide  in  the  market  contains  a  slight  trace  of  chloride.  A 
small  quantity,  such  as  half,  up  to  one  per  cent.,  is  of  no  consequence  so  long  as  an  excess 
of  soluble  bromide  is  present.  If,  however,  the  bromide  and  silver  nitrate  exist  exactly 
in  their  combining  proportions,  chloride  of  silver  is  formed;  and  the  same  result  obtains 
if  the  silver  is  in  excess. 

Printing  with  Gelatino-bromide  or  Gelatino-chloride  of  Silver  without  Development. — An 
ordinary  gelatino-bromide  plate  darkens  in  a  few  seconds  under  the  action  of  light,  and, 
if  exposed  under  a  negative  for  some  hours,  a  picture  full  of  detail  is  obtained,  which, 
however,  disappears  in  the  fixing  bath.  By  fuming  the  plates  with  carbonate  of  ammonia, 
the  darkening  proceeds  much  more  rapidly,  and  denser  pictures  can  be  obtained.  In 


414        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

make  that  substitute  for  collodion  answer.  The  work  began  with  the  manu- 
facturers of  gelatine,  who  by  careful  experiment  conquered  all  difficulties  and 

producing  prints  by  this  method  an  emulsion  containing  an  excess  of  silver  is  preferable 
to  one  containing  an  excess  of  bromide,  as  the  former  darkens  more  rapidly  under  the 
action  of  light.  Such  plates,  if  previously  fumed  with  ammonia,  can  be  employed ;  but 
a  longer  exposure  must  be  given  than  when  ordinary  albumenized  paper  is  employed. 

Gelatino  chloride  ot  silver  for  printing  without  development  should  also  contain  an 
excess  of  silver,  and  requires  an  exposure  of  several  hours.  The  prints  are  brownish-red 
in  color,  and  can  be  toned  with  gold. 

Emulsions  prepared  with  a  large  excess  of  silver  are  not  subject  to  decomposition.  By 
long  keeping,  however,  they  are  apt  to  discolor,  owing  to  a  reduction  of  silver. 

Testing  Gelatine  Negatives  before  Varnishing. — It  is  always  well  to  take  a  print  from  a 
gelatine  negative  before  varnishing,  in  order  to  judge  whether  intensification  is  necessary. 
This  can  always  be  done  if  the  negative  is  thoroughly  dry ;  otherwise  red  stains  are  apt 
to  make  their  appearance.  Mr.  England  is  in  the  habit  of  laying  a  piece  of  talc  between 
the  negative  and  the  albumenized  paper  to  protect  the  film. 

Retouching  can  be  carried  out  on  gelatine  negatives  if  necessary  before  varnishing,  if  a 
small  quantity  of  turpentine  be  rubbed  over  the  film  in  order  to  give  a  tooth  to  the  pencil. 
It  is  safer,  however,  to  varnish  the  film  first. 

Removing  the  Varnish  from  Gelatine  Negatives. — This  operation  is  often  necessary  when 
varnished  negatives  require  intensification.  It  can  readily  be  done  by  soaking  the  plate 
in  strong  spirit  of  benzine,  which  dissolves  the  varnish,  and  the  plate  may  then  be  gently 
wiped  clear  of  the  varnish  with  a  tuft  of  cotton-wool. 

Recovery  of  Silver  from  Waste  Emulsion. — For  this  purpose  the  emulsion  may  be  boiled 
for  a  short  time  with  from  one-third  to  one-sixth  of  its  volume  of  a  strong  lye  of  soda  or 
potash  and  grape  sugar.  When  the  mass  blackens  throughout,  owing  to  the  reduction 
of  silver,  and  becomes  fluid,  water  is  added,  and  the  mixture,  after  being  allowed  to  settle, 
is  decanted.  The  precipitated  silver  can  be  heated,  and  melted  into  a  globule.  This 
method  is  also  suitable  for  collodion  emulsion.  The  silver  may  also  be  recovered  by 
boiling  the  emulsion  or  treating  it  cold  with  hydrochloric  acid,  which  decomposes  the 
gelatine,  and  when  the  silver  has  separated  to  the  bottom  of  the  vessel,  the  liquid  may 
be  decanted  off.  The  best  method,  however,  that  I  am  acquainted  with,  is  the  following: 
To  every  100  parts  of  emulsion  10  parts  of  concentrated  sulphuric  acid  diluted  with  100 
parts  of  water  are  added.  The  mixture  is  boiled  in  an  earthenware  jar  for  ten  or  twenty 
minutes.  The  bromide  of  silver  becomes  granular,  and  after  the  solution  has  been  diluted 
with  an  equal  bulk  of  water  it  settles  to  the  bottom  of  the  vessel.  The  liquid  may  then 
be  poured  off,  and  the  precipitate  thrown  on  to  a  filter  and  allowed  to  dry.  As  this 
operation  is  unaccompanied  by  any  disagreeable  escape  of  gas,  it  is  preferable  to  the 
preceding. 

Cleaning  off  Old  Films. — This  is  a  matter  of  greater  difficulty  with  gelatine,  than  with 
collodion  plates.  The  former  may  be  soaked  in  a  solution  of  chromic  acid,  or  in  a  warm 
solution  of  soda.  The  latter  decomposes  the  gelatine,  and  the  films  can  then  be  readily 
detached  by  washing.  The  plates  should  be  soaked  in  a  bath  of  weak  hydrochloric  acid, 
to  remove  any  trace  of  alkali,  and  then  rinsed. 


NEGATIVE-MAKING  —  DRY.  415 

produced  an  article  that  met  all  the  wishes  of  the  emulsion  maker,  as  rapidly  as 
it  became  possible  to  do  so. 

Increasing  the  Sensitiveness  of  Gelatino- Bromide  Plates  by  Fuming. — Plates  which  have 
been  exposed  to  the  fumes  of  strong  ammonia  at  ordinary  temperatures,  immediately 
before  exposure,  will  develop  rapidly  either  with  alkaline  pyrogallic,  or,  after  rinsing, 
with  ferrous  oxalate,  and  give  pictures  full  of  detail.  This  method  should  be  useful  in 
studio  work. 

Keeping  Qualities  of  Gelatine  Plates  during  the  Summer  Months,  and  the  Value  of  Anti- 
septics.— It  has  often  been  remarked  that  gelatine  emulsion  which  has  been  kept  for  some 
time  becomes  fluid ;  and  the  value  of  the  bromide  of  silver  becomes  ruined  for  photo- 
graphic purposes.  In  order  to  prevent  this  process  of  decomposition,  the  addition  of 
antiseptics,  such  as  carbolic  acid,  thymol,  salicylic  acid,  etc.,  has  been  recommended. 
Experience  on  this  point  is  rather  conflicting.  Szekely  finds  that  an  emulsion  treated 
with  thymol  or  salicylic  acid  is  equally  liable  to  decomposition  during  the  hot  weather. 
On  the  other  hand,  we  noticed  that  while  an  emulsion  containing  no  antiseptic  becomes 
fluid  after  three  days,  another  in  which  thymol  or  salicylic  acid  was  incorporated  kept 
sound  for  six  or  eight  weeks,  so  long  as  it  was  not  subjected  to  a  high  temperature. 
General  experience  is  in  favor  of  the  fact  that  both  thymol  and  carbolic  acid  are  better 
than  salicylic  acid  for  preserving  emulsions  for  decomposition. 

The  Function  of  an  Excess  of  Soluble  Bromide  or  Chloride  in  an  Emulsion. — The  fact  is 
familiar  that  an  excess  of  soluble  bromide  restrains  the  attainment  of  the  highest  sensi- 
tiveness in  bromide  of  silver,  and  that  an  emulsion  containing  a  large  excess  of  bromide, 
if  insufficiently  washed,  is  insensitive,  and  the  reverse  if  thoroughly  washed.  The  same 
fact  obtains  in  the  case  of  a  collodion  emulsion.  In  reference  to  this,  Wetzlar  remarked 
as  early  as  1827  that  chloride  of  silver  in  a  solution  of  sodium  chloride  becomes  converted 
into  a  double  salt,  which  is  affected  by  light,  whether  it  be  in  a  moist  or  dry  condition. 
If  an  emulsion  is  prepared  with  a  large  excess  of  soluble  bromide  or  chloride,  the  slightly 
sensitive  double  salt  is  formed,  and  it  is  only  by  thorough  washing  that  it  can  be  decom- 
posed. We  may  consequently  infer  from  this  the  necessity  of  thoroughly  washing  an 
emulsion  which  has  been  prepared  with  a  large  excess  of  soluble  chloride  of  bromide. 
The  value  of  a  large  excess  of  soluble  bromide  or  chloride  lies  in  the  fact  that  it  restrains 
any  possible  decomposition  of  the  gelatine  which  may  arise  during  the  preparation  of 
the  emulsion. 

The  Value  of  Gelatine  in  Preventing  the  Precipitation  of  Bromide  or  Chloride  of  Silver. — 
Hecht  has  described  some  experiments  that  he  made  with  a  view  of  determining  this 
point.  A  solution  of  silver  nitrate  was  added  to  a  simple  solution  of  a  metallic  chloride 
or  bromide,  as  well  as  to  solutions  of  the  same  to  which  gelatine  had  been  added  until 
turbidity  in  the  solution  denoted  a  precipitation  of  chloride  of  silver.  The  results  were 
as  follows: 

(a)  100  parts  of  a  1  per  cent,  solution  of  sodium  chloride  at  a  temperature  of  39°  C.  or 
40°  C.  retained  in  solution  .00954  part  silver  chloride. 

(6)  100  parts  of  a  1  per  cent,  solution  of  sodium  chloride  to  which  5  per  cent,  gelatine 
had  been  added  retained  at  the  same  temperature  .05736  part  silver  chloride. 


416        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Success  came  through  much  tribulation  and  trial,,  but  since  it  came  what 
marvels  have  transpired. 

(c)  100  parts  of  a  1  per  cent,  solution  potassium  bromide  retained  at  a  temperature  of 
39°  C.  and  40°  C.  .01099  part  bromide  of  silver. 

(d]  100  parts  of  the  same  to  which  5  per  cent,  gelatine  had  been  added  retained  .05950 
part  bromide  of  silver. 

These  experiments  indicate  that  the  presence  of  gelatine  retards  to  a  certain  extent  the 
formation  of  the  haloid  salts  of  silver.  Practically,  a  solution  containing  5  per  cent, 
gelatine  retains  five  times  as  much  as  a  solution  in  which  no  gelatine  is  present.  After 
the  solution  has  cooled  down,  and  has  stood  for  some  time,  a  small  portion  of  the  salt 
separates  out. 

On  the  Gradual  Increase  of  Sensitiveness  in  Emulsions  by  Keeping. — Captain  Abney  and 
Mr.  England  have  stated  that  an  emulsion  goes  on  increasing  in  sensitiveness,  and  that 
plates  coated  from  an  emulsion  which  has  been  kept  for  fourteen  days  are  twice  as  sen- 
sitive as  when  the  latter  is  used  fresh.  In  the  case  of  an  emulsion  made  with  either 
gum  or  gelatine,  which  contains,  in  the  first  instance,  the  insensitive  modification  of 
bromide  of  silver,  no  amount  of  keeping  will  produce  any  appreciable  increase  of  sensi- 
tiveness. It  is  only  when  an  emulsion  is  extremely  sensitive  at  first,  that  keeping  at 
ordinary  temperatures  produces  any  increase  of  sensitiveness.  An  emulsion  prepared 
with  ammonia  gains  in  sensitiveness  very  much  if  it  is  allowed  to  stand  for  twenty-four 
hours  before  washing. 

In  order  to  obtain  films  of  uniform  thickness,  the  best  way  is  to  determine  how  much 
emulsion  is  required  per  square  inch  of  surface  in  order  to  give  a  fairly  thick  film,  and  to 
measure  out  the  necessary  amount  each  time;  in  general,  0.04  to  0.06  c.  c.  suffice  per 
square  centimetre. 

Relief  Exhibited  in  Gelatine  Plates  after  Fixing. — An  appearance  of  relief  is  often  ob- 
served in  gelatine  plates  after  development  with  ferrous  oxalate,  and  is  very  apparent  in 
places  where  strong  contrasts  of  light  and  shade  exist  in  close  proximity.  It  may  be 
possible  to  turn  this  fact  to  account  in  various  photo-mechanical  processes,  in  the  same 
way  that  Scamoni  employed  it  with  collodion  plates. 

On  the  Proper  Strength  of  the  Fixing  Bath. — A  very  strong  solution  of  hyposulphite  of 
soda  appears  to  act  very  slowly,  owing  probably  to  the  difficulty  with  which  it  penetrates 
into  the  film.  It  will  often  be  sufficient  in  such  a  case  to  flow  pure  water  over  the  film, 
when  the  fixing  will  proceed  rapidly.  The  correct  proportions  of  the  fixing  bath  are 
about  1  to  5  or  10.  Cyanide  of  potassium  and  sulpho-cyanide  of  ammonium  are  not  to 
be  recommended  for  fixing  gelatine  plates.  If  the  fixing  solution  is  too  strong  it  attacks 
the  silver,  and  leaves  a  thin,  useless  picture. 

Substrata  for  Gelatine  Plates. — If  an  emulsion  has  a  tendency  to  frill,  and  it  is  decided 
not  to  correct  the  emulsion  itself,  the  best  method  is  to  coat  the  plates  with  the  following 
substratum :  1  part  of  gelatine  is  dissolved  in  300  parts  warm  water,  filtered,  and,  when 
cool,  6  parts  of  a  filtered  1.50  solution  of  chrome  alum  is  added.  The  plate%  are  washed, 
and,  while  still  wet,  the  chrome  alum  and  gelatine  solution  is  flowed  off  and  on.  The 
first  coating  will  mix  with  the  water,  and  a  second  coating  may  be  flowed  on,  and  the 


NEGATIVE-MAKING  —  DRY.  417 

There  are  more  successes  to  come  provided  the  mantle  of  noble  generosity, 
which  led  the  experimenters  of  the  past  to  give  of  their  knowledge,  falls 
upon  their  artistic  and  earnest  successors. 

plate  allowed  to  dry.  It  is  somewhat  difficult  to  flow  emulsion  over  plates  prepared  in 
this  way.  The  best  way,  perhaps,  is  to  place  the  plates  on  a  levelled  support,  and  to 
guide  the  emulsion  up  to  the  edges  with  a  strip  of  glass.  A  solution  of  water-glass 
(sodium  silicate)  1 :  200  may  also  be  employed  for  the  same  purpose.  A  very  useful  sub- 
stratum may  be  prepared  by  mixing  3  or  4  parts  water-glass  with  7  or  8  parts  albumen^ 
and  80  to  100  parts  of  water.  The  plates  are  washed,  and,  after  draining,  are  coated 
with  the  substratum.  Forrest  recommends  in  the  Photographic  Almanack,  the  following 
solution:  The  white  of  one  egg  is  mixed  with  500  grammes  of  water,  to  which  30 
grammes  methylated  spirit  and  20  drops  of  carbolic  acid  have  been  added.  The  solu- 
tion, after  filtering,  can  be  kept  for  months,  and  has  been  found  a  perfect  cure  against 
frilling. 

The  Sensitiveness  of  Bromide  of  Silver  under  the  Action  of  Different  Forms  of  Developers. — 
Vogel  made  some  experiments  with  his  new  emulsion  in  reference  to  the  above,  and 
found  that,  by  the  use  of  acid  development,  customary  with  wet  plates,  the  emulsion  was 
five  times  as  sensitive  as  wet  collodion,  and  considerably  more  so  than  collodion  dry 
plates  prepared  with  excess  of  potassium  bromide.  Ferrous  sulphate  as  a  developer  did 
not  give  a  better  result  than  pyrogallic  acid.  Ordinary  collodio-bromide  plates  are  three 
times  as  sensitive  when  treated  with  a  pyrogallic  chemical  developer,  as  when  treated 
with  the  same  in  the  form  of  a  physical  developer. 

The  Use  of  Alum  or  Chrome  Alum  in  Emulsions. — These  substances  may  be  added  to  an 
emulsion,  either  to  improve  its  setting  power,  or  to  prevent  any  tendency  to  frill.  The 
same  result  can  be  obtained  by  placing  the  plate,  after  development,  and  before  fixing, 
into  a  concentrated  solution  of  alum.  The  alum  bath  used  after  fixing  is  recommended 
for  hardening  the  gelatine,  as  well  as  to  destroy  any  traces  of  hyposulphite  of  soda  which 
may  remain  in  the  film.  The  brown  color  often  present  in  a  negative  after  development 
with  alkaline  pyrogallic  can  easily  be  removed  by  soaking  the  plate  for  a  short  time  in  a 
concentrated  solution  of  alum,  to  which  1-32  of  its  volume  of  hydrochloric  acid  has  been 
added.  Mr.  Carroll  and  Captain  Abney  claim  that  a  gelatine  plate  which  has  been 
soaked  in  a  concentrated  solution  of  alum  can  be  intensified  with  silver  without  difficulty. 

Treatment  of  the  Gelatino- Bromide  Image  as  in  Carbon  Printing. — Warnerke  has  found 
that  an  image  upon  gelatino-bromide,  developed  with  pyrogallol,  is  insoluble  in  warm 
water.  Such  an  image  may,  therefore,  be  transferred,  and  further  developed,  just  as  if  it 
were  upon  bichromated  pigment  tissue.  But,  as  pyrogallic  acid  hardens  the  film,  the 
water  for  developing  must  be  hot,  or  contain  a  little  alkali;  fixed  with  hyposulphite,  the 
film  is  more  easily  dissolved.  An  image  thus  treated  may  also  be  used  for  collotypic 
printing,  ammonia  applied  to  the  surface  before  inking  assuring  clear  prints. — DE. 
J.  M.  EDER. 

27 


CHAPTEE   XVI. 

NEGATIVE-MAKING "PAPER"  AND  "  FILM." 

176.  DURING  the  many  years  that  collodion  held  its  place  in  the  dark-room 
its  difficulties  and  defects  came  to  be  accepted  as  the  necessary  adjuncts  of  a 
process  which,  after  all,  combined  most  of  the  qualities  desirable  in  a  negative 
process.  It  was  simple  and  inexpensive,  comparatively  quick,  and  left  little 
to  be  desired  in  chemical  effect. 

When  the  extraordinary  sensitiveness  of  gelatino-bromide  of  silver  became 
known,  new  possibilities  were  revealed,  and  that  quality  of  itself  proved  suffi- 
cient to  enable  the  new  process  to  oust  the  old  after  a  struggle.  But  the 
enthusiastic  photographer  is  never  content.  Flushed  by  his  success  in  throwing 
off  the  bath  and  collodion,  he  asks  for  more — a  substitute  for  glass.  He  feels 

176.  After  exposure,  of  course,  the  method  of  treatment  is  similar  to  that  of  the  dry 
plate.  It  is  best,  in  hot  weather,  to  use  ice  in  the  developer  and  the  wash  water. 

In  treating  negative  paper  prepare  the  developer  as  follows : 

No.  1. — Sulphite  of  sodium  crystals,  pure,  6  ounces;  distilled  or  boiled  water,  1  quart; 
pyrogallic  acid,  1  ounce.  No.  2.— Carbonate  of  soda,  pure,  i  pound ;  water,  1  quart. 

To  develop  take  in  a  suitable  tray  No.  1,  1  ounce;  No.  2,  1  ounce;  water,  1  ounce. 

Immerse  the  exposed  paper  in  clean  cold  water  and  with  a  soft  camel's-hair  brush 
gently  remove  the  adhering  air  bells  from  the  surface.  As  soon  as  limp  transfer  to  the 
developer,  taking  care  to  avoid  bubbles  by  gently  lowering  the  paper  by  one  edge  so  as 
to  slide  it  under  the  surface  of  the  developer. 

The  image  should  appear  in  10  to  20  seconds  and  the  development  should  be  carried 
on  in  the  same  way  as  for  a  glass  dry  plate.  If  the  image  appears  too  quick  and  is  flat 
and  full  of  detail  add  5  to  10  drops  of  the  restrainer — Bromide  potassium,  1  ounce ;  water, 
6  ounces.  This  will  keep  back  the  shadows  and  allow  the  high  lights  to  attain  density. 

If  the  exposure  has  been  too  short  and  the  image  does  not  appear  except  in  the  highest 
lights,  add  instead  of  the  restrainer  not  to  exceed  one  ounce  of  No.  2 ;  this  will  help  to 
bring  out  the  details  and  compensate  in  a  measure  for  the  short  exposure.  As  soon  as 
sufficient  density  is  obtained  slightly  rinse  the  negative  and  put  it  in  the  fixing-bath — 
Hyposulphite  of  soda,  4  ounces;  water,  1  pint;  common  alum,  £  ounce.  To  be  mixed 
fresh  for  each  batch  of  negatives. 

The  completion  of  the  fixing  operation  may  be  ascertained  by  looking  through  the  film. 
When  fixed  wash  in  5  or  6  changes  of  water  for  15  or  20  minutes  and  then  lay  the  paper 
negative  face  down  upon  a  sheet  of  polished  hard  rubber.  Press  the  negative  into  con- 
(418) 


NEGATIVE-MAKING  —  PAPER    AND    FILM.  419 

hampered  in  the  free  use  of  gelatine  dry  plates  by  their  cost.  Everything 
conspires  to  render  gelatine  dry  plates  expensive.  Until  this  is  corrected  we 
can  scarcely  be  said  to  have  a  perfect  negative  process. 

There  are,  however,  two  methods  now  coming  into  use  which  promise  well. 
First  a  little  as  to  their  history,  and  then  instructions  how  to  use  them. 

While  many  another  ingenious  plodder  was  experimenting  with  gelatine 
sheets  and  translucent  paper,  reviving  the  old  Talbotype  process,  or  treading 
on  the  heels  of  the  manufacturers  of  carbon  tissue,  Mr.  George  Eastman  turned 
aside  from  all  makeshifts,  and  attacked  the  conundrum  in  an  entirely  different 
direction,  in  \vhich  he  met  with  the  success  he  deserves. 

One  of  Mr.  Eastman's  products  is  an  emulsion  film  supported  on  paper  or  its 
equivalent,  and  is  supplied  to  the  purchaser  either  in  "  endless "  rolls,  or  in 
"  blocks  "  of  a  dozen  or  more  sheets  together,  flat  and  compact. 

I  am  hardly  called  upon  to  go  into  the  details  of  the  manufacture  of  these 
films,  for  the  possible  processes  are  various.  There  are  methods  given  further 
on.  Given  the  "  film,"  what  concerns  us  most  is,  how  are  we  to  make  it 
available  ? 

tact  with  the  plate  by  the  scraping  action  of  a  squeegee,  and  allow  to  dry,  when  it  will 
peel  off  from  the  plate  with  a  fine  polished  service. 

The  Oxalate  Developer. — This  developer  also  works  well  with  negative  paper,  and  I 
recommend  it  for  trial — Saturated  solution  oxalate  of  potash,  6  ounces ;  saturated  solu- 
tion protosulphate  of  iron,  1  ounce.  The  separate  solutions  keep  well  and  should  be 
mixed  fresh  for  development  and  about  25  per  cent,  of  old  developer  added  for  use. 

To  render  the  paper  negative  translucent  so  that  it  will  print  quickly,  lay  it  face  down 
upon  a  clean  piece  of  paper  and  rub  over  the  back  a  liberal  quantity  of  translucine ; 
allow  it  to  soak  into  the  paper  until  it  is  of  an  even  dark  color.  This  will  take  four  or 
five  hours  in  a  moderate  warm  room.  Then  wipe  off  the  surplus  with  a  squeegee  and 
afterward  with  a  soft  cloth.  The  negative  is  then  ready  to  print.  If  the  negative  is 
wanted  for  immediate  use  the  action  of  the  translucine  may  be  accelerated  by  heat. 

Castor  oil  has  heretofore  been  recommended  for  making  paper  negatives  translucent, 
but  after  an  extended  series  of  experiments  I  have  adopted  a  preparation  which  has  no 
odor  and  does  not  require  the  use  of  a  hot  iron  to  make  it  sink  into  the  paper. 

Thus  prepared,  negative  paper  will  print  remarkably  free  from  grain  and  quicker  than 
most  pyro  and  ammonia  developed  glass  negatives.  To  print  simply  lay  the  negative 
with  the  glossy  side  up  on  a  piece  of  glass  in  the  printing  frame,  lay  upon  it  the  positive 
paper  and  print  the  same  as  a  glass  negative.  The  negative  does  not  require  fastening 
to  the  glass  in  any  way.  These  negatives  should  be  kept  between  paraffine  paper,  or 
back  to  back  in  a  printing  frame,  or  suitable  box.  If  the  translucine  dries  out  after 
continued  use,  the  negative  may  be  given  a  fresh  application. 

When  the  negative  is  to  be  retouched,  as  in  portraiture,  it  should  be  done  after  oiling. 


420         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Were  the  paper  or  other  support  simply  coated  with  sensitized  emulsion, 
there  would  be  no  profitable  way  of  utilizing  it  for  negative  purposeSo  Refer 
to  the  diagram  (Fig.  334)  and  this  fact  will  be  made  plain.  A  is  the  support ; 

(7  is  the  layer  of  emulsion ;  and  B  is  a  gelatine  layer 

c          '       '  which  comes  in  between  for  a  purpose  which  will  be 

A  .j^^^^^^^^^r*    found  necessary  when  the  method  of  using  the  film 

is  further  explained. 

The  construction  of  the  film  is  now  understood,  and  we  expose  it  in  the 
camera.  It  is  developed  and  fixed  as  though  it  were  on  glass.  After  being 
thoroughly  washed,  the  film  is  detached  from  the  paper  in  the  following,  or  in 
some  equivalent,  manner : 

The  fixed  and  washed  film  is  floated  face  downward  in  water,  and  a  glass 
plate  being  introduced  under  it  and  lifted  out  of  the  water,  the  plate  will  lift 
the  film  with  it,  which  is  then  made  to  adhere  closely  to  its  surface  by  pressure 
on  the  back  of  the  paper.  The  adhesion  is  preferably  secured  by  the  sliding 
pressure  of  the  edge  of  a  straight  piece  of  rubber  or  other  flexible  substance 
carried  along  the  back  of  the  film.  The  application  of  the  pressure  should  be 

The  paper  takes  the  pencil  freely  and  persons  unskilled  will  find  it  comparatively  easy 
to  "work." 

When  it  is  necessary  to  intensify  it  may  be  done  before  oiling  by  soaking  the  negative 
in  a  saturated  solution  of  corrosive  sublimate,  washing  and  then  blackening  the  image 
with  a  solution  of  10  drops  of  strong  ammonia  per  ounce  of  water. 

Where  strong  negatives  are  desired  add  5  drops  of  the  restrainer  to  the  developer  before 
using. 

The  negatives  may  be  printed  without  rendering  transparent.  The  only  advantage  in 
oiling  is  to  make  the  negative  print  quicker,  the  grain  of  the  paper  being  imperceptible, 
either  with  or  without  oiling.  When  a  negative  is  not  to  be  oiled,  it  is  a  good  plan  to 
coat  it  on  both  sides  with  plain  collodion.  This  gives  the  paper  a  glazed  surface  and 
prevents  it  getting  soiled  in  printing.  The  best  way  to  apply  the  collodion  is  to  immerse 
the  negative  in  it  in  a  shallow  tray  for  the  instant,  remove  and  hang  up  by  one  corner  to 
dry. — GEO.  EASTMAN. 

Having  heard  many  complaints  of  paper  negatives  curling,  and  being  hard  to  handle 
in  the  printing  frame,  etc.,  I  have  concluded  to  give  my  way  of  managing  them,  as  I  am 
using  them  right  along  for  all  sizes  from  5x7  up,  with  fine  success,  and  am  greatly  in  love 
with  them,  on  account  of  their  very  many  advantages  over  glass. 

Develop  as  per  directions  (I  carry  the  development  a  little  further  than  with  glass); 
When  developed  rinse  in  clean  water,  then  fix  in  hypo  and  water,  leave  out  the  alum. 
When  thoroughly  fixed,  which  is  shown  by  the  negative  being  of  a  uniform  color,  looking 
through  it,  or  simply  showing  the  grain  of  paper  with  no  opaque  spots,  wash  and  immerse 
in  a  saturated  solution  of  alum  for  five  minutes.  Wash  thoroughly  and  squeegee  face 


NEGATIVE-MAKING — PAPER    AND    FILM.  421 

repeated  until  contact  is  •  secured  at  all  points  by  the  entire  removal  of  the 
water  between  the  glass  and  the  film.  The  paper  support  is  now  detached 
from  the  film  by  the  application  of  the  requisite  degree  of  heat  to  the  glass 
plate,  the  effect  of  which  is  to  soften  the  gelatine  layer  between  the  paper  and 
the  relatively  insoluble  gelatine  layer  containing  the  image,  so  that  the  paper 
may  be  readily  stripped  off  or  removed,  leaving  the  image  adhering  to  the  glass. 
The  heat  may  be  applied  uniformly  by  placing  the  glass  on  a  heated  plate  of 
metal,  or  on  a  water  bath,  or  by  the  application  of  hot  water  to  the  plate.  Any 
remaining  traces  of  the  soluble  gelatine  layer  may  be  sponged  or  washed  off 
with  warm  water,  and  the  glass  and  adhering  film,  when  dried  and  varnished, 
if  desired,  is  ready  for  the  printer. 

By  the  use  of  wax  on  the  glass  or  other  support,  the  film  may  be  stripped 
and  used  or  preserved  independently.  Thus  the  glass  having  been  coated,  with 
beeswax  dissolved  in  turpentine,  and  subsequently  polished,  the  gelatine  image 
may  be  removed  therefrom  by  applying  a  moist  gelatine  sheet  to  it  and  allow- 
ing it  to  dry,  after  which  the  two  gelatine  sheets  may  be  removed  together 
from  the  glass  or  other  support,  and  may  be  subsequently  used  to  print  from, 
or  mounted,  or  preserved  in  any  preferred  manner. 

The  operation  may  be  performed  in  different  order.     Thus,  the  paper  may 

down  on  a  sheet  of  ebonite.  When  thoroughly  dry  it  will  peel  off,  giving  a  beautiful 
glossy  face  (I  prefer  using  the  alum  solution  after  fixing,  as  it  gives  a  clearer  and  cleaner 
negative  than  when  mixed  with  the  hypo).  The  negative  will  invariably  curl  face  in  on 
being  lifted  from  the  ebonite,  and  may  be  straightened  by  the  scraping  action  of  a  ruler 
applied  to  the  back.  Lay  the  negative  on  a  sheet  of  glass  with  a  clear  piece  of  paper 
between  the  negative  and  glass.  Apply  the  ruler,  the  corner  behind  the  ruler  being 
lifted  as  the  ruler  is  passed  along.  When  straight,  lay  face  down  on  a  piece  of  smooth 
pine  board  (with  a  piece  of  clean  paper  on  it),  and  tack  the  four  corners  with  thumb 
tacks.  Apply  the  "  trauslucine"  or  oil,  and  hold  over  the  oil-stove,  keeping  the  negative 
in  motion  till  it  presents  a  uniform  dark  color  all  over.  (The  board  keeps  the  negative 
from  curling  as  it  would  do  if  not  tacked  to  the  board  when  heat  is  applied.)  When  cool 
repeat  the  operation.  I  repeat  it  because  one  is  then  sure  it  is  transparent,  and  it  takes 
but  a  moment  to  do  it.  When  cool  the  secqnd  time,  wipe  off  the  surplus  oil  with  a  clean 
rag.  The  retouching  can  be  done  from  either  side.  If  from  face,  I  apply  the  retouching 
fluid  with  the  ball  of  the  finger  same  as  with  a  glass  negative.  If  from  the  back  no 
preparation  is  necessary,  simply  use  a  harder  pencil. 

I  keep  the  negative  in  place  in  the  printing  frame  by  tacking  the  corners  with  small 
pieces  of  sticking  paper.  For  copies  one  can  do  four  times  the  amount  of  retouching 
that  can  be  done  on  glass — working  out  backgrounds,  etc.  In  storing  away  for  further 
use  I  oil  a  piece  of  paper  in  the  same  way  I  oil  the  negatives.  Place  it  between  two 
negatives  (back  to  back).  This  keeps  the  negatives  saturated  a  long  time,  not  allowing 


422        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

be  stripped  from  the  film  before  development  or  after  development,  and  before 
fixing  or  after  fixing. 

I  ought  to  have  said  as  to  the  gelatines  in  the  composition  of  the  gelatine 
layer  C,  and  the  emulsion  layer  B,  that  the  last  is  less  soluble  than  the  first 
(though  both  are  insoluble  in  cold  water),  because  of  the  addition  of  chrome 
alum,  and  is  rendered  so  in  order  that  it  may  be  transferred  to  glass  or  entirely 
detached  from  any  support,  if  preferred,  as  described  above. 

The  matter  will  be  made  still  plainer  if  I  quote  the  claims  of  the  inventor: 

"  I  claim,  as  a  new  article  of  manufacture,  a  sensitive  photographic  film 
consisting  of  a  coating  of  insoluble  sensitized  gelatine,  C;  a  paper  or  equivalent 
support,  A ;  and  an  interposed  coating  of  soluble  gelatine,  J5." 

Or,  to  be  mdre  definite,  as  a  new  article  of  manufacture,  a  sensitive  photo- 
graphic film  composed  essentially  of  a  paper  or  equivalent  support,  a  film  of 
sensitized  gelatine,  and  an  interposed  attaching-film,  the  said  sensitized  film 
being  insoluble,  and  the  said  intermediate  attaching-film  being  insoluble  with 
respect  to  the  developing-fluids,  but  rendered  soluble  in  water  by  the  applica- 
tion of  heat,  substantially  as  described. 

them  to  dry  out.  It  is  easier  to  oil  the  separating  paper,  than  it  is  to  have  to  re-oil  two 
negatives. — W.  B.  GLINES. 

As  my  work  is  largely  in  the  line  of  paper  negatives,  I  may  be  excused  for  confining 
myself  to  this  subject. 

Not  unfrequently  have  I  read  of  various  mediums  being  recommended  for  drying  the 
negative  upon,  to  enable  one  when  they  are  dry  to  strip  them  off  straight  and  smooth, 
and  it  has  led  me  to  believe  that  others  may  have  as  much  trouble  as  I  have  had.  It 
cannot  be  questioned  that  polished  hard  rubber  is  the  best  known  medium,  but  where  a 
large  number  of  prints  are  to  be  mounted  at  one  time,  rubber  is  too  expensive.  I  have 
always  used  glass,  but  many  a  good  negative  have  I  scraped  off  with  my  knife,  being 
unable  to  pull  it  off,  even  though  it  was  well  greased.  I  have  tried  ferrotype  plates,  as 
has  been  recommended,  but  without  success. 

I  have  discovered  that  polished  glass  is  much  better  than  ordinary  French  glass,  and 
I  have  also  found  that  it  is  better  to  rub  it  thoroughly  with  whiting,  let  it  dry,  and  then 
polish  clean,  than  to  wash  it.  I  use  an  oil  made  by  combining  sperm  oil  and  fresh 
lard  to  the  consistency  of  cream. 

But  with  almost  any  support  they  are  apt  to  dry  uneven,  the  upper  part  (if  set  in  a 
rack)  will  dry  first,  and  leave  the  support,  causing  the  paper  to  cockle  up  and  prevent 
lying  flat  in  the  printing  frame.  This  is  very  annoying,  as  I  have  been  obliged  in 
some  instances  to  wet  them  and  mount  them  over.  This  difficulty  is  very  much  lessened 
by  setting  the  negatives  up  in  a  rack  until  surface-dry,  then  place  one  or  two  blotting- 
pads  between  them,  lying  flat  on  the  table  over  night ;  in  the  morning,  set  them  up  in 
the  rack  again,  and  dry  slowly.  This  is  the  best  way  I  know  of  to  proceed  with  oiled 


NEGATIVE-MAKING  —  PAPER    AND    FILM.  423 

177.  When  Mr.  Eastman  was  working  the  process  described  above  in  con- 
nection with  his  friend  and  partner,  Mr.  William  H.  Walker,  they  found  that 
when  the  support  was  coated  on  one  side  only,  the  coating  would  swell  from 
the  absorption  of  water  during  the  various  stages  of  development,  and  the 
films  would  consequently  manifest  a  tendency  to  curl  backward.  Patient 
experiment  revealed  the  fact  that  this  annoyance  could  be  overcome  by  giving 
the  support  a  coating  of  gelatine  on  its  back  or  reverse  side.  A  new  invention 
was  thus  born,  and  jointly  the  gentlemen  named  have  received  a  second  patent 
for  process  and  product.  Fig.  335  represents  the  film  as  it  is  now  offered  to 
the  trade.  S  represents  the  flexible  sup-  -$IG.  335. 

port;  E,  the  sensitive  coating;  L,  the 
interposed  gelatine  layer;  and  5,  the 
gelatine  backing. 

In  practice,  the  emu^ion  layer  containing  the  image  may  be  stripped  from 
the  flexible  support  by  the  application  of  warm  water,  which  dissolves  the 
interposed  gelatine  layer  Ly  and  the  detached  film  may  then  be  used  alone  or 
affixed  to  any  suitable  support  for  printing  purposes.  The  second  new  method, 
then,  is  the  art  of  preparing  sensitive  photographic  films,  the  process  consisting 

I  have  recently  discovered  what  I  believe  to  be  a  more  satisfactory  way  than  oiling, 
although  I  speak  from  less  experience.  In  experimenting  with  Eastman's  stripping 
films  I  used  a  rubber  solution  which  they  supply ;  it  is  usually  flowed  over  each  plate, 
and  allowed  to  set  before  the  negative  is  adjusted ;  but  this  being  too  tedious  for  a  num- 
ber of  prints,  I  took  one  of  my  oiled  plates  and  wiped  it  off  as  thoroughly  as  I  could,  and 
with  a  piece  of  chamois  skin,  dampened  with  the  rubber  solution,  I  went  quickly  over 
the  plate  and  adjusted  the  negative  at  once.  It  remained  in  perfect  contact  until  thor- 
oughly dry,  and  then  I  cleaned  the  glass  with  a  fine  surface  and  without  a  wrinkle.  I 
have  no  doubt  it  would  have  done  the  same  had  not  the  glass  been  previously  oiled.  I 
shall  investigate  further,  and  if  what  I  have  written  will  help  anyone,  I  shall  feel  repaid 
for  giving  my  experience. — C.  M.  FRENCH. 

177.  To  make  gelatine  film  negatives,  I  give  you  several  methods. 

Preparation  of  the  Negative  Film. — Ordinary  white  writing  paper  is  allowed  to  lie  for  a 
short  time  in  water,  then  placed  "upon  a  clean  glass  plate,  which  has  been  previously 
rubbed  with  a  little  wax,  and  bordered  around  with  strips  of  albumen  or  gum  paper. 
When  the  paper  is  dry,  it  is  stretched  tightly  over  the  plate,  and  sprinkled  over  with 
talc  powder ;  the  excess  of  powder  is  brushed  off  with  a  cameFs-hair  pencil.  The  paper 
is  now  coated  with  a  mixture  of— Ether,  50  grammes ;  alcohol,  50  grammes ;  pyroxylin, 
1  gramme ;  oil  of  ricinus,  8  drops. 

As  soon  as  the  collodion  is  perfectly  set,  the  bromide  of  silver  gelatine  emulsion  is 
spread  over  smoothly  by  means  of  a  glass  rod.  As  soon  as  the  emulsion  is  set,  the  edges 
are  cut  round  by  a  penknife,  and  the  film  easily  lifted  up  and  cut  to  any  desired  size. 


424         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

in  applying  to  a  sheet  of  paper,  or  like  support,  a  layer  of  soluble  gelatine  and 
drying  the  same,  then  calendering  the  sheet  to  harden  and  polish  its  surface, 
and  finally  applying  to  the  soluble  layer  of  the  calendered  sheet  a  coating  of 
relatively  insoluble  gelatino-argentic  emulsion.  These  are  known  in  the  trade 
as  "American  films."  The  inventors  prefer  to  attach  the  film  to  a  glass 
support  before  removing  the  paper,  as  described  by  Mr.  Eastman  in  his 
individual  patent. 

As  I  have  already  said,  the  manufacturers  supply  both  the  new  films  and 
negative  paper  in  "  blocks "  of  a  dozen  or  more,  or  upon  rollers  containing 

sufficient  film  for  fifty  or  more  exposures. 
Those  preferring  them  in  blocks,  can  remove 
them  film  by  film,  and  use  them  backed  with 
glass. in  the  ordinary  holder.  Or  a  "film 
carrier  "  (Fig.  336)  is  ^provided.  This  last  is 
made  so  light  and  strong,  that  with  the  film 
attached  it  may  be  placed  in  any  holder  as  though  it  were  a  sheet  of  glass.  Its 
use  is  obvious. 

For  greater  facility  in  their  use,  a  roll-holder  may  be  attached  to  the  camera. 
At  one  end  of  the  holder  a  roll  of  film  is  inserted,  and  its  loose  end  drawn 

Another  method  consists  in  coating  over  the  same  kind  of  paper  or  albumen  paper  laid 
upon  a  warm  plate  with — Wax,  2  parts ;  benzine,  100  parts. 

The  paper  so  prepared  is  dampened,  and,  as  in  the  former  recipe,  stretched  over  a 
clean  glass  plate,  and  coated  with  the  gelatine  emulsion.  This  plan  affords  more  brilliant 
results  than  the  former ;  besides,  the  sensitive  film  seems  to  adhere  firmer  to  the  paper, 
a  circumstance  desirable  for  the  subsequent  manipulations  to  which  it  is  to  be  subjected. 

A  third  method :  A  sheet  of  double  transportation  paper  is  stretched  over  a  glass  plate, 
and  coated  with  collodion  as  before;  and,  after  setting,  separated  from  the  glass.  A 
second  glass  plate  is  sprinkled  with  talc  powder,  coated  with  emulsion,  and  laid  after 
the  setting  of  the  gelatine  (about  a  quarter  of  an  hour)  in  a  dish  of  distilled  water.  The 
collodionized  paper  is  also  laid  in  another  dish  of  water,  and  when  wet  through,  laid 
upon  the  gelatine  plate,  the  collodion  surface  against  the  gelatine  film.  The  plate  and 
paper  are  now  taken  from  the  water,  and  contact  thoroughly  secured  by  means  of  gentle 
pressure.  The  paper  is  now  cut  around  the  edges  of  the  glass,  and,  if  properly  per- 
formed, the  gelatine  film  will  detach  itself  from  the  glass  and  be  found  adhering  to  the 
paper,  in  which  condition  it  is  ready  for  exposure  in  the  camera.  In  separating  the  film 
from  the  glass,  care  must  be  taken  to  do  it  quickly  and  without  any  pause,  otherwise 
there  is  danger  of  tearing  the  film. 

Fourth  method :  Ordinary  white  paper  or  albumen  paper  is  waxed  as  before,  and  the 
glass  plate  strewn  with  talc  powder,  coated  with  gelatine,  and,  after  the  setting,  together 
with  the  paper  put  in  the  water  bath.  If  both  are  carefully  taken  out,  it  will  be  found 


NEGATIVE-MAKING  —  PAPER    AND    FILM. 


425 


FIG.  337. 


across  and  fastened  to  a  roller  on  the  other  side.  After  the  first  exposure  is 
made  a  light  and  peculiar  system  of  machinery  within  the  holder  is  then  wound 
up,  and  set  in  motion.  Thus,  the  film  is  drawn  across  the  face  of  the  holder 
until  a  given  signal  is  sounded,  when  the  works  halt,  and  the  film  is  ready  for 
another  exposure,  and  so  on  to  the  end  of  the  film.  A  method  of  registering 
the  exposures  is  supplied,  and  a  puncture  is  made  in  the  film  automatically,  as 
the  film  moves  from  roller  to  roller,  to  show  where  one  exposure  ends  and 
another  begins.  The  drawing  makes  it  very  plain  (Fig.  337).  It  consists 
essentially  of  a  metal  frame 
carrying  the  spool  wound 
with  the  supply  of  paper,  and 
a  reel  for  winding  up  the  ex- 
posed paper,  suitable  devices 
for  maintaining  a  tension  upon 
the  paper,  and  measuring  and 
registering  mechanism.  Th-3 
frame  is  hinged  at  both  ends 
to  the  panelled  board  which 
forms  the  back  of  the  enclosing  case.  The  cut  shows  the  holder  with  the  case 
partly  raised.  The  movement  raised  for  changing  the  spool  is  shown  in  Fig. 

that  the  two  surfaces  are  in  contact,  and  all  that  is  necessary  is  to  separate  them.  This 
process  avoids  the  coating  of  the  paper  with  collodion,  as  in  the  first  method.  These 
leaves  or  films  may  be  preserved  in  a  book,  so  as  to  keep  them  flat. 

Development.— -The  films  are  laid  in  distilled  water,  and  suffered  to  lie  there  until  they 
become  perfectly  flat.  The  water  is  then  poured  oif  and  the  developer  applied.  When 
the  shadows  of  the  negative  begin  to  appear  gray,  the  developer  is  poured  off,  the  negative 
well  washed  and  put  in  a  bath  of  hypo  and  alum,  where  it  is  allowed  to  remain  until  all 
the  unreduced  bromide  of  silver  is  eliminated,  which  is  indicated  by  the  paper  becoming 
pure  white.  The  negative  is  then  washed  for  hours.  If  it  is  desirous  to  have  a  firm, 
inflexible  negative,  take  a  glass  plate  sprinkled  with  talc,  and  coat  it  with  collodion; 
then,  after  the  setting,  with  a  mixture  of— Water,  100  parts;  white  gelatine,  40  parts. 
As  soon  as  this  sets,  treat  the  plate  to  a  bath  of  water.  In  the  same  bath  place  the 
negative  film ;  let  it  remain  therein  about  five  minutes,  and  press  it  in  contact  with  the 
gelatinized  glass.  The  attached  film  is  allowed  to  dry  thoroughly,  and  the  paper  cut 
about  6  mm.  from  the  edge  with  a  penknife.  The  paper  is  loosened  from  the  plass  plate. 
If  a  thin  film  is  needed,  the  glass  plate  is  sprinkled  with  the  talc  and  coated  with  col- 
lodion. The  negative  is  dipped  in  a  thin  gelatine  solution,  laid  upon  the  collodionized 
plate,  and  the  excess  of  gelatine  pressed  out.  The  whole  is  allowed  to  dry  and  the  paper 
detached,  and  the  negative  film  from  the  paper,  in  the  same  manner  as  before  described. 
An  evil  attached  to  the  method  is,  that  the  negative  film,  curls  up  too  easily. 


426 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG  338. 


338.  To  fill  the  holder,  the  movement  is  raised,  the  spool  inserted  in  its  place 
under  the  brake  and  fastened  with  the  thumb-screw  on  the  side  of  the  frame ; 
the  pawl  on  the  tension  barrel  is  thrown  off,  the  bank  on 
the  spool  broken,  and  sufficient  paper  drawn  out  to  reach 
over  the  bed  to  the  reel ;  the  movement  is  shut  down  and 
fastened  and  raised  at  the  reel  end,  the  paper  is  then 
drawn  over  the  guide  roll  and  slipped  under  the  clamp  on 
the  reel,  and  the  reel  turned  sufficiently  to  give  the  clamp 
a  hold  on  the  paper.  Now,  throw  in  the  pawl  on  the 
tension  drum  and  put  on  the  tension  by  turning  the 
tension  barrel  over  to  the  left  until  the  paper  is  taut ; 
shut  down  the  movement  and  put  on  the  case,  insert  the 
key  and  turn  it  over  until  the 
alarm  strikes  once,  draw  the  slide 
and  mark  the  limits  of  the  first 
exposure  with  a  lead-pencil.  The 
holder  is  then  ready  to  attach  to 
the  camera.  After  the  first  exposure  turn  the  key  until  the  alarm  strikes  four 
times  (three  in  the  4x5  holder).  This  brings  a  fresh  sheet  on  the  bed  for 

The  paper  negative  may  be  dried  between  blotting  paper,  but  must  be  first  treated  to 
an  alum  bath.  It  is  then  well  washed  and  flooded  in  a  mixture  of— Water,  1000  parts ; 
glycerine,  50  parts ;  alcohol,  50  parts ;  by  which  means  the  films  become  soft  and  flexible. 

Of  the  above  methods  for  preparation  of  negative  films,  I  especially  recommend  the 
third  and  fourth  as  giving  very  brilliant  negatives,  without  spots  or  pinholes.  Although 
the  methods  may  occasion  some  little  trouble,  I  think  that  the  photographer  will  be  richly 
repaid  for  the  labor  expended. — ROBERT  CHENEVIERE. 

For  the  "American  films"  the  manipulations  vary  somewhat  from  those  for  the 
negative  paper. 

Development. — No.  1.  Sulphite  of  sodium,  pure,  6  ounces ;  distilled  or  boiled  water,  1 
quart ;  pyrogallic  acid,  1  ounce. 

Dissolve  the  sulphite  first  and  then  add  the  pyro.  No.  2.  Carbonate  of  soda,  pure, 
}  pound ;  water,  1  quart; 

To  develop  pour  into  a  clean  tray  the  following :  No.  1,  1  ounce ;  No.  2,  1  ounce ; 
water,  1  ounce. 

Immerse  the  exposed  film  in  a  tray  of  clean  cold  water,  and  with  a  soft  camel's-hair 
brush  gently  remove  the  air  bells  that  cling  to  the  surface  of  the  film.  As  soon  as  limp, 
remove  the  film  to  the  tray  containing  the  developer  and  proceed  with  the  development 
the  same  as  with  a  dry  plate.  The  image  should  commence  to  appear  in  ten  or  fifteen 
seconds.  If  the  lights  come  slowly  and  with  no  detail  in  the  shadows,  add  not  to  exceed 
one  ounce  of  No.  2.  If  the  image  appears  too  quickly,  add  10  to  20  drops  of  the  restrainer 


NEGATIVE-MAKING  —  PAPER    AND    FILM.  427 

exposure,  after  which  turn  the  key  and  make  as  many  exposures  as  required. 
When  done,  take  the  holder  into  the  dark-room,  remove  the  case  and  insert 
the  point  of  a  penknife  in  the  slot  in  the  guide  roll  and  separate  the  exposed 
from  the  unexposed  by  drawing  it  along  the  slot.  -  Throw  off  the  pawl  from 
the  reel  and  draw  out  the  exposed  paper  and  cut  it  off  at  every  fourth  mark 
(third  mark  in  the  4x5  holder),  with  a  pair  of  shears.  If  any  unexposed 
paper  remains  on  the  spool  draw  over  the  end  and  attach  it  to  the  reel  as  before, 
and  the  holder  is  ready  for  work  again. 

This  is  a  most  ingenious  and  satisfactory  arrangement,  and  proves  the  con- 
sideration of  the  inventors  in  not  only  giving  us  a  new  product,  and  a  new 
process,  but  in  producing  the  wherewithal  to  make  its  use  easy,  certain,  and 
therefore  enjoyable.  The  roll-holder,  for  fifty  films,  weighs  one  pound  less 
than  two  ordinary  double  holders  filled. 

Here  is  a  great  advantage  among  a  hundred  others.  The  inventor  modestly 
states  but  &  few  in  his  specifications,  as  follows : 

— Bromide  of  potassium,  1  ounce ;  water,  6  ounces.  Keep  this  in  a  dropping  bottle 
consisting  of  an  ordinary  bottle  having  two  notches  cut  lengthwise  in  the  cork,  on 
opposite  sides. 

The  film  may  be  examined  from  time  to  time  by  transmitted  light  by  holding  it  up  by 
the  corners.  When  sufficient  density  is  obtained,  wash  the  film  in  two  changes  of  cold 
water  and  then  immerse  in  the  fixing  bath — Hyposulphite  of  soda,  4  ounces ;  water,  1 
pint. 

Mix  fresh  fixing  bath  for  each  batch  of  negatives.     Use  no  alum  in  the  fixing  bath. 

Films  fix  quicker  than  glass  dry  plates,  and  the  completion  of  the  operation  can  be 
ascertained  by  the  even,  translucent  appearance  from  the  back  while  lying  in  the  bath 
or  by  examination  by  transmitted  light. 

Oxalate  Developer. — The  oxalate  of  iron  developer  works  well,  and  has  no  tendency  to 
attack  the  soluble  substratum  and  render  it  insoluble.  No.  1.  Oxalate  of  potash,  1 
pound ;  hot  water,  3  pints. 

Acidify  with  sulphuric  acid.  Test  with  litmus  paper.  No.  2.  Protosulphate  of  iron, 
1  pound;  hot  water,  1  quart;  sulphuric  acid,  £  drachm. 

No.  3.  Bromide  of  potassium,  1  ounce ;  water,  1  quart. 

To  develop,  take  of  No.  1,  6  ounces;  No.  2,  1  ounce;  No.  3,  10  drops.  Mix  in  the 
order  given ;  use  cold. 

After  exposure,  soak  the  paper  in  water  until  limp,  then  immerse  in  the  developer. 

The  image  should  appear  slowly,  and  should  develop  up  strong,  clear,  and  brilliant. 
When  the  shadows  are  sufficiently  black,  wash  well  and  fix. 

After  fixing,  wash  in  three  or  four  changes  of  cold  water  for  five  or  ten  minutes,  and 
the  film  is  then  ready  for  transferring  to  glass.  Coat  a  clean  glass  plate,  one  size  larger 
than  the  film  with  the  following  rubber  solution :  Eastman's  pure  para  gum,  5  grains  ; 
benzine,  1  ounce. 


428         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

"  The  advantages  which  the  sensitized  films  possess  over  the  ordinary  glass 
dry  plates  are  obvious.  Thus,  one  is  enabled  to  dispense  entirely  with  the 
glass,  the  original  cost,  and  the  expense  arising  from  the  handling,  cleaning, 
breakage,  and  transportation  of  which  is  saved;  also  to  effect  a  considerable 
economy  in  the  amount  of  emulsion  used,  as  the  glass,  owing  to  its  curvature 
and  uneven  surface,  requires  to  be  coated  thicker  than  the  gelatinized  paper  ; 
and,  as  the  operation  of  coating  the  gelatinized  paper  with  the  emulsion,  may 
in  manufacturing  operations  be  carried  on  by  machinery  in  absolute  darkness, 
the  highest  sensitiveness  may  be  given  to  the  emulsion  employed  in  the  im- 
proved films  without  danger  of  fog  from  too  much  light ;  and  the  operations 
necessary  to  secure  the  desired  image  are  so  simple  as  to  be  readily  learned  by 
the  most  inexperienced  person." 

When  dry,  slip  the  plate  under  the  negative,  which  should  be  face  down  in  a  tray  of 
water.  Grasp  the  film  by  one  edge  on  the  glass  and  lift  from  the  water,  allowing  the 
water  to  drain  from  the  side  furthest  from  the  operator.  All  surplus  waterman  now  be 
removed  by  the  scraping  action  of  a  rubber  squeegee,  and  the  plate  supporting  the  film 
set  aside  to  dry.  When  dry,  soak  the  film  and  plate  in  a  dish  of  warm  water,  increasing 
the  temperature  until  the  paper  commences  to  blister.  Lift  one  corner  of  the  paper  with 
the  point  of  a  pin  and  gently  pull  it  off  from  the  negative  film,  which  will  adhere  to  the 
glass.  Eemove  from  the  film  with  warm  water  all  traces  of  the  soluble  substratum  which 
is  between  the  paper  and  the  film. 

The  image-bearing  film  is  now  on  the  glass  with  the  paper  removed.  If  intensification 
should  be  necessary,  the  operation  can  be  performed  in  the  same  manner  as  with  dry 
plates. 

Intensification. — Soak  the  plate  in  a  saturated  solution  of  bichloride  of  mercury,  until 
the  image  turns  a  dull  gray  color;  wash  thoroughly  and  apply  a  weak  solution  of  am- 
monia, say — Strong  water  ammonia,  10  drops;  water,  1  ounce. 

The  plate  may  now  be  dried  and  proofs  taken  or  retouching  done ;  or  it  may,  without 
drying,  be  immediately  prepared  for  stripping  from  the  glass  by  coating  with  the 
stripping  varnish— Clear  white  gelatine,  £  pound;  glycerine,  800  grains;  carbolic  acid 
solution,  1  ounce;  water,  40  ounces. 

Carbolic  acid  solution.  Carbolic  acid  crystals,  2  ounces  ;  alcohol,  4  ounces ;  water,  2 
ounces. 

Soak  the  gelatine  in  the  water  until  soft,  dissolve  by  heat,  and  add  the  glycerine  and 
carbolic  acid  solution.  Filter  carefully,  and  allow  to  stand  in  warm  water  until  the 
bubbles  disappear.  This  preparation  will  keep  indefinitely  and  can  be  melted  for  use. 
In  damp  climates  the  proportion  of  glycerine  may  be  reduced. 

Coat  the  film  on  the  plate  thickly  with  the  hot  gelatine  varnish  and  put  on  a  level 
shelf  to  set.  When  dry,  cut  around  the  edge  of  the  film  with  a  sharp  knife  and  peel  the 
film  negative  from  the  glass.  Remove  the  adhering  thin  film  of  rubber  with  the  palm 
of  the  hand  dry  or  a  bit  of  cotton  moistened  with  benzine.  The  film  is  now  ready  for 
printing. 


NEGATIVE-MAKING  —  PAPER    AND    FILM.  429 

178.  Since  these  inventions  have  been  introduced  European  and  other  manu- 
facturers and  experimenters  have  been  busied  in  perfecting  the  processes  by 
which  they  may  be  worked  with  most  success. 

The  printing  of  a  film  negative  may  be  done  from  either  side  if  required,  but  the  side 
that  was  next  to  the  glass  is  the  correct  side.  The  film  should  be  laid  on  a  piece  of 
ground  glass  in  the  printing-frame  with  the  rough  side  of  the  glass  next  the  film.  This 
gives  fine,  soft  effect  and  prevents  mottling  of  the  paper  caused  by  partial  contact  of  the 
film  with  the  glass. 

In  general.  Solutions  used  in  developing  the  films  should  not  exceed  75°  Fahr.,  and 
the  hands  should  only  touch  them  at  the  corners  while  wet  to  prevent  softening  of  the 
soluble  gelatine  layer  that  holds  the  film  on  the  paper. 

Alum  must  not  be  used  on  the  films  or  in  any  of  the  solutions,  lest  the  soluble  gelatine 
layer  be  rendered  insoluble  and  prevent  subsequent  transfer. 

For  photo-mechanical  printing  processes  and  carbon  single  transfer,  the  films  may  be 
printed  while  on  the  glass. 

It  has  been  found  that  when  the  ammonia  developer  is  used,  or  if  the  proportion  of 
sulphite  in  the  formula  given  is  increased,  there  is  a  liability  of  the  pyrogallic  acid 
attacking  the  soluble  gelatine  layer  and  rendering  it  insoluble.  I  therefore  guarantee 
the  stripping  of  the  films  only  when  the  developer  used  is  mixed  according  to  formula 
and  all  directions  are  strictly  followed. — GEORGE  EASTMAN. 

178.  M.  Thiebaulfs  Support  for  Emulsion  Films. — The  chief  difference  between  this 
emulsion  and  others  in  the  market  lies  in  the  fact  that  it  is  spread  on  cardboard;  the 
cardboard  is  first  enamelled,  which  enables  emulsion  to  be  spread  over  it  evenly,  and  to 
adhere  thereto  with  sufficient  tenacity  to  enable  it  to  bear  the  ordinary  processes  of 
exposure,  development,  fixing,  and  washing  with  impunity.  After  these  processes  have 
gone  through,  the  emulsion  remaining  on  the  cardboard  can  be  detached  therefrom,  and 
the  photograph  is  then  left  on  a  clean,  perfectly  transparent,  and  tough  sheet  of  gelatine, 
from  which  prints  can  be  taken  from  either  side.  Thus  the  weight  of  glass,  the  chance 
of  breaking,  and  imperfections  arising  from  a  process  in  which  a  paper  base  has  to  be 
made  transparent,  are  avoided. 

Development. — This  is  done  either  by  oxalate  or  pyrogallic  acid,  in  accordance  with  the 
known  processes  repeated  hereafter. 

Pour  the  developing  liquid,  which  must  be  prepared  in  a  graduated  glass  measure 
beforehand,  over  the  card. 

The  white  or  bright  parts  of  the  negative  enable  the  operator  to  watch  the  progress  of 
the  development,  which  must  be  allowed  to  go  on  long  enough,  because  of  the  great 
transparency  of  the  film. 

After  having  poured  back  the  developing  liquid,  without  removing  the  negative,  rinse 
it  twice  in  water,  which  should  be  changed  each  time. 

Pyrogallic  Acid  Developer. — Solution  A.  Water,  1000  parts;  carbonate  of  potash,  45; 
sulphite  of  soda,  12. 

Solution  B.     Water,  1000;  pyrogallic  acid,  12;  sulphite  of  soda,  12;  citric  acid,  2. 

Mix  an  equal  quantity  of  Solution  A  with  Solution  B,  and  place  the  card  in  the  mix- 
ture as  soon  as  it  is  made. 


430         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

Efforts  have  been  made,  too,  to  improve  and  push  forward  old  inventions. 
Likewise  other  and  new  methods  of  supplying  a  substitute  for  glass  have  been 

Ferrous  Oxalate  Developer. — Solution  A.  Warm  water,  1000 ;  neutral  oxalate  of  pot- 
ash, 300;  bromide  of  potassium,  3.  (To  be  filtered.) 

Solution  B.     Warm  water,  500 ;  ordinary  ferrous  sulphate,  200. 

After  solution  add  3  c.  c.  of  sulphuric  acid  in  order  to  prevent  oxidation. 

Mix  80  c.  c.  of  Solution  A  with  20  c.  c.  of  Solution  B.  This  developer  may  be  used  for 
developing  successively  two  or  three  negatives. 

Fixing. — Place  the  card  in  the  fixing  bath,  taking  care  that  the  image  be  turned  down- 
wards. It  requires  about  a  half  an  hour  in  order  that  the  operation  be  well  done. 

Several  negatives  can  be  fixed  in  the  same  bath,  provided  there  be  liquid  enough. 

After  this,  two  hours  of  washing  are  sufficient,  during  which  the  water  should  be 
changed  three  or  four  times. 

The  following  formula  should  be  strictly  observed :  Warm  water,  hyposulphite  of  soda, 
ordinary  pulverized  alum.  Let  this  solution  settle  for  several  hours,  and  then  filter  it. 

Drying. — This  operation  is  very  simple.  After  having  cleaned  the  surface  of  the  film 
with  a  piece  of  wet  cotton,  dry  it  several  times  between  sheets  of  blotting  paper,  and  then 
fix  it  firmly  on  a  board  by  means  of  four  or  six  pins,  the  image  being  turned  toward  a 
sheet  of  blotting  paper. 

It  is  only  after  being  completely  dry  (this  is  very  important]  that  the  gelatine  film  can 
be  detached  from  the  card  by  raising  it  at  one  corner,  and  round  the  edges,  previously 
being  careful  to  remove  the  holes  made  by  the  pins. — INCE  and  ADDENBROOKE. 

M.  Balagny's  Flexible  Gelatino-bromide  Plate. — Contemporary  with  the  invention  of 
M.  Thiebault,  is  the  method  of  Mons.  G.  Balagny  of  Paris.  The  ingenious  experiment- 
alist has  been  working  in  an  entirely  different  direction  from  those  who  found  it  quite 
easy  to  manufacture  a  support  of  small  size  from  a  combination  of  castor  oil  and  collo- 
dion, and  now  supplies  a  flexible  body  "as  colorless  and  transparent  as  glass."  It  is 
composed  of  a  succession  of  very  adhesive  films  of  collodion,  varnish,  and  gelatine.  Each 
one  of  the  substances  employed  gives  one  or  more  of  the  qualities  desirable  in  the  result, 
namely,  transparency,  flexibility,  impermeability,  and  extensibility. 

M.  Balagny  admits  some  trifling  difficulties  in  the  manipulation  of  his  films,  owing  to 
the  disposition  of  gelatine  to  "take  in  water,"  but  these  he  will  entirely  overcome.  For 
all  classes  of  work  he  recommends  them,  and  gives  the  following  details  of  manipulation : 

To  develop,  use  a  dish  made  of  oak,  having  a  glass  bottom  and  a  glass  opening  on  one 
of  the  longer  sides.  The  bottom  of  this  dish  is  wet  with  a  little  water,  which  is  entirely 
removed.  There  remains  enough  dampness  to  cause  the  plate  to  adhere.  The  bath,  as 
usual,  is  in  a  glass  vessel,  and  is  thrown  on  the  plate,  which  has  been  placed  on  the  bot- 
tom of  the  dish.  The  development  is  made  with  either  iron  or  pyrogallic  acid,  with 
ammonia,  carbonates,  etc.  M.  Balagny  says :  "  I  make  use  of  the  development  with  soda 
crystals,  which  I  have  before  mentioned,  and  I  obtain  agreeable  tones  with  entire  absence 
of  the  yellow  color  which  causes  many  persons  to  avoid  the  use  of  pyrogallic  acid.  What- 
ever the  mode  employed,  the  development  goes  on  exactly  as  if  it  were  a  glass  plate  ; 
neither  slower  nor  quicker.  There  is  no  necessity  for  hurry  or  fear,  as  it  is  with  great 


NEGATIVE-MAKING  —  PAPER    AND    FILM.  431 

offered,  the  most  promising  of  which  are  herein  considered  with  the  hope  that 
some  good  may  be  found  in  them  and  lead  to  more. 

At  this  writing  the  adoption  of  films  is  not  general  enough  to  enable  me  to 

difficulty  that  the  liquid  can  penetrate  the  support.  From  time  to  time  the  dish  is  lifted 
so  as  to  bring  all  the  bath  in  the  space  formed  by  the  cover,  and  it  is  possible  to  follow 
from  second  to  second  the  progress  made  in  the  development  by  examining  the  cliche  by 
transparency.  This  is  a  point  that  I  have  always  held,  and  that  I  have  always  wished 
to  see  realized  by  any  support  whatever,  for  to  develop  by  reflection  without  being  able 
to  follow  the  development  by  transparency,  is  to  go  at  haphazard ;  it  is  to  create  another 
difficulty  when  photography  already  presents  so  many,  and  to  yield  up  everything  to 
chance.  If  necessary,  the  negative  is  strengthened  by  any  of  the  known  means;  then, 
when  it  has  reached  the  desired  point,  it  is  placed  for  two  or  three  minutes  in  a  six  per 
cent,  alum  bath.  Now  fix  in  a  fifteen  or  twenty  per  cent,  hypo  bath,  then  wash  in  five 
or  six  consecutive  waters,  allowing  the  cliche  to  remain  in  each  from  five  to  ten  minutes. 
The  oftener  the  water  is  changed,  the  better  the  negative  is  washed.  However,  do  not 
allow  the  negatives  to  remain  too  long  in  the  last  water ;  in  one  hour  all  should  be  ended. 
I  have  sometimes  allowed  negatives  to  remain  in  the  water  three  hours  in  succession  ; 
but  this  is  useless,  as  it  is  the  change  that  does  the  washing.  It  is  therefore  possible,  by 
frequently  changing  the  water,  to  wash  very  quickly,  and  that  without  handling  the 
negatives.  All  the  negatives  being  in  the  same  dish,  the  water  which  it  contains  is 
poured  out  by  one  of  the  corners ;  the  negatives  remain  at  the  bottom,  and  the  water  is 
renewed. 

Here  too  is  a  method  which  promises  much,  but  it  is  not  just  what  we  want.  The  total 
depravity  of  gelatine,  better  known  to  dry-plate  makers  than  to  the  users  of  plates,  has 
made  it,  if  not  as  objectionable  on  account  of  brittleness,  yet  fully  as  much  so  on  account 
of  its  susceptibility  to  atmospheric  changes.  We,  therefore,  want  something  that  will 
enable  us  to  dispense  with  both  glass  and  gelatine.  It  will  probably  come  to  us  some 
day,  with  a  substitute  for  albumen. 

The  placing  in  the  frames  is  very  simple.  Stretchers  are  very  good  but  not  necessary. 
We  may  gum  the  upper  and  lower  edges  of  a  plate  of  glass,  of  wood,  of  metal,  or  even 
of  cardboard,  and  the  flexible  plate,  which  is  exceedingly  plane,  will  stretch  on  this  plate 
without  the  least  difficulty.  A  fortiori,  sticking  plaster  may  be  used  with  perfect  success. 
The  rapidity  is  the  same  as  for  the  best  plates.  It  is,  therefore,  possible  to  make  por- 
traits, groups,  and  instantaneous  views.  It  is  known  that  certain  kinds  of  work  give 
what  is  called  halos.  Such  are  the  interiors  lighted  by  plain  or  painted  glass,  the  sky 
detaching  itself  on  a  background  of  trees,  and  strong  whites  alongside  of  blacks  in  the 
subject;  in  these  cases,  it  is  customary,  to  prevent  the  double  reflection  of  the  luminous 
rays,  to  coat  the  reverse  of  the  plates  with  a  mixture  of  burnt  sienna,  earth,  and  dextrine. 
Now  s  as  we  have  here  a  body  absolutely  similar  to  glass,  it  is  probable  that  the  same 
thing  might  be  reproduced. 

I  will  here  make  an  observation  applicable  to  alum  and  hyposulphite  baths,  and  to 
the  washings.  In  all  these  cases  the  kind  of  dish  to  be  used  is  immaterial.  Stiffened 
cardboard  is  very  suitable.  It  is  well  during  these  operations  that  the  gelatine  film 


432         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

quote  largely  from  the  experiences  of  my  co-laborers.  But  so  it  was,  at  first, 
with  bromo-gelatine  plates.  Film  photography  will  grow. 

should  be  turned  toward  the  bottom  of  the  dish,  whilst  in  the  developing  bath  the  film 
which  forms  the  negative  should  always  be  on  top. 

When  the  washings  are  ended,  the  clich6  is  quickly  passed  through  bibulous  paper, 
used  solely  for  this  purpose,  to  remove  the  excess  of  water,  and  finally  plunged  for  five 
minutes  in  the  following  bath,  contained  in  an  enamelled  sheet-iron  or  glass  dish  : 
Alcohol  at  40°  (95  per  cent.),  16>  ounces  7  drachms ;  glycerine,  1  ounce  5  drachms. 

This  bath  has  for  its  object  to  accelerate  the  drying  and  to  give  very  great  flexibility  to 
the  negative. 

You  now  remove  your  negative  from  the  bath,  drain  it  for  half  a  minute  over  the  dish, 
and  place  it  between  two  sheets  of  thick  bibulous  paper,  laid  on  a  clean  plate,  or  even  on 
the  plate  itself  without  any  bibulous  paper.  Place  on  the  back  of  the  negative  a  sheet 
of  rubber  or  oil-cloth,  and  with  a  roller  gently  press  to  remove  all  excess  of  the  liquid. 
After  using  one  sheet  of  bibulous  paper,  should  any  humidity  remain,  change  it ;  you 
thus  dry  your  negative,  keeping  it  flat  on  a  plate  and  pressing  over  it  the  roller  with  the 
interposition  of  one  or  two  sheets  of  thick  bibulous  paper.  When  all  apparent  humidity 
has  disappeared,  that  which  is  not  visible  and  which  is  in  the  body  of  the  plate,  is 
removed  by  placing  it  for  half  an  hour  between  thick  bibulous  paper  laid  flat  on  a  table, 
<  r,  when  travelling,  at  the  bottom  of  the  dish,  which  should  be  carefully  wiped.  In  a 
word,  the  negative  should  be  kept  perfectly  plane  whilst  drying,  but  there  is  no  need  for 
any  support.  Placed  between  a  book  of  bibulous  paper  on  a  table  or  between  plates  of 
glass,  or  books,  the  result  is  the  same.  At  the  end  of  half  an  hour  or  one  hour,  and  to 
render  the  negative  very  plane,  it  is  placed  in  a  bound  album  of  the  thick  bibulous  paper 
mentioned  above,  in  which  it  may  be  allowed  to  remain  indefinitely.  When  the  album 
is  full,  the  negatives  are  laid  one  over  the  other  in  piles,  or  are  placed  in  a  spring  box 
such  as  is  used  for  the  preservation  of  positive  paper.  There  is  nothing  to  fear  from 
scratches  or  rubbing,  the  new  support  being  solid.  When  the  bath  has  been  used  several 
times  it  becomes  excellent ;  but  from  use  it  diminishes,  and  then  some  n.ew  bath  should 
be  added  in  the  proportion  of  two  to  one.  A  bath  is  old  when  a  small  quantity  placed 
in  the  flame  of  a  candle  takes  fire  with  difficulty.  It  should  always  weigh  about  60  degrees 
with  a  centesimal  alcohometer.  Four,  five,  or  even  more  negatives  may  be  placed  in 
the  bath  at  the  same  time.  In  this  case,  and  after  they  have  remained  five  minutes, 
they  are  placed  one  over  the  other  on  a  single  plate ;  finish  by  using  a  sheet  of  oil-cloth 
or  caoutchouc.  When  the  roller  is  used  all  the  liquid  exudes  and  is  received  in  the 
dish.  Then,  with  thick  bibulous  paper,  each  negative  is  separately  dried,  still  making 
use  of  the  roller.  The  negatives  are  then  placed  one  after  the  other  in  the  first  blotter, 
and  then  in  the  last,  in  which  they  remain  until  required  for  use. 

With  this  process  carbon  printing  is  very  simple,  requiring  but  one  transfer.  Positives 
by  transparency  are  made  with  very  great  rapidity,  and  projections  and  stereos,  notably, 
show  a  clearness  worthy  of  albumen. 

Finally,  as  the  flexible  plates  do  not  stretch,  they  can  be  used  for  printing  two  super- 
posed negatives,  one  giving  a  greatly  exposed  landscape,  and  the  other,  persons  who 


NEGATIVE-MAKING  —  PAPER    AND    FILM. 


433 


For  interiors  flexible  negatives  are  far  preferable  to  anything  else,  because 
halation  is  an  almost  unknown  occurrence  with  them  under  any  circumstances. 

posed  instantaneously.  With  little  practice  it  will  be  possible  to  develop  these  negatives 
lightly,  although  with  all  the  details,  so  that  in  printing  one  of  the  two  negatives,  the 
bottom  one  should  receive  the  light  only  through  the  other. 

Before  glass  dry  plates  have  reached  the  perfection  which  was  hoped  for,  it  is  already 
sought  to  replace  them  in  most  of  their  applications  by  the  pellicular  processes.  I  am 
convinced  that  these  new  preparations  will  be  solely  used  in  the  future.  But  to  supplant 
glass  plates,  they  should  possess  the  same  qualities — fineness,  transparency,  rapidity,  and 
regularity — without  the  objections  to  such  plates — their  fragility  and  weight.  This  is  a 
very  complex  problem,  and  up  to  the  present  time  only  very  unsatisfactory  substitutes 
have  been  offered.  Most  of  the  pellicular  processes  lack  rapidity,  which  is  a  serious 
obstacle  in  the  matter  of  instantaneousness.  Moreover,  some  are  not  sufficiently  rigid, 
and  placing  them  in  the  frame  is  more  or  less  difficult ;  others,  on  the  contrary,  owing  to 
the  presence  of  a  cardboard  support,  are  sufficiently  rigid  and  plane,  but  completely 
opaque.  Under  these  conditions,  development  is  uncertain ;  and  anyone  desirous  of 
obtaining  an  irreproachable  cliche*,  may  well  hesitate  in  operating  in  this  manner. 
Finally,  the  pellicle  may  swell  in  the  divers  liquids  and  present  enlargements  or  dis- 
tortions.—M.  BALAGNY. 

We  have  recently  examined  a  new  process  due  to  our  friend,  M.  Balagny.  This 
process  seems  to  us  the  most  perfect  of  any  that  exists.  It  consists  of  the  use  of  a  sen- 
sitive pellicle  obtained  by  special  processes,  and  possessing  the  following  qualities: 
absolute  transparency,  inextensibility,  great  delicacy,  and  sufficient  rapidity  for  the 
requirements  of  current  instantaneous  photography.  It  requires  no  support,  and  may  be 
printed  on  both  sides,  which  is  important  for  carbon  reproductions  and  those  made  with 
fatty  inks.  In  one  thing  it  is  deficient,  namely,  it  is  not  sufficiently  rigid  to  be  used  in 


FIG.  339. 


FIG..  340. 


the  frames  like  glass  plates.     This  difficulty  may  be  overcome  if  we  can  stretch  by  any 
practical  means  this  pellicle,  to  which  the  inventor  has  given  the  name  of  flexible  plate 

28 


434         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

For  landscapes  and  for  some  kinds  of  architectural  work  they  are  full  of 
advantages. 

A  word  of  caution  as  to  development.  Do  not  be  misled  by  the  appearance 
of  a  paper  negative  under  the  developer.  It  is  rarely  as  dense  as  it  looks. 
As  a  rule  further  pushing  is  needed  than  with  a  negative  on  glass.  Again, 
after  a  flexible  negative  has  been  fixed  it  will  be  found  that  greater  reduction 
has  taken  place  than  would  be  the  case  with  a  glass  plate.  The  process  of 
rendering  the  film  transparent  also  reduces  the  density  of  the  high  lights,  and 
causes  greater  contrast  with  the  shadows. 

Certainly  there  is  so  much  that  is  desirable  in  a  properly  made  pellicular 
negative  that  our  ingenious  and  industrious  experimentalists  will  not  rest  until 
they  have  mastered  all  the  difficulties  attendant  upon  their  production. 

The  appliance  for  obtaining  this  result  was  not  easy  to  make ;  we  must  admit,  however, 
that  it  has  been  found  by  M.  Dessoudeix.  This  appliance  is  called  a  stirator,  and  is 
composed  of  a  perforated  steel  plate  of  the  size  of  the  flexible  plate  used.  The  edges  are 
furnished  with  points  at  a  distance  of  one  centimetre  (T%  of  an  inch)  from  each  other 
(Fig.  339). 

To  affix  the  pellicle  to  the  stirator,  a  hinged  box  is  used  (Fig.  340).  On  the  inside  of 
this  box  and  on  one  of  its  sides,  the  pellicle  is  placed ;  on  the  other,  the  stirator,  the 
centre  of  which  is  deflected  in  order  to  fasten  it  to  a  catch  placed  in  the  central  portion 
of  the  box.  The  box  is  now  closed,  using  slight  pressure.  In  this  operation  the  points 
perforate  the  pellicle,  and  when  the  box  is  opened  it  has  been  transferred  and  fixed  to 
the  stirator.  By  loosening  the  catch  the  centre  of  the  stirator  is  again  straightened, 
owing  to  the  elasticity  of  the  metal,  and  the  sheet  is  stretched  in  the  most  perfect 
manner.  The  stirator,  thus  provided,  is  used  in  all  the  cases  where  glass  plates  are  made 
use  of. — ALBERT  LONDE. 


CHAPTER   XYII. 

RETOUCHING   AND    "DOCTORING"    THE   NEGATIVE. 

179.  THIS  subject  is  so  fully  treated  in  Wilson's  Photographies  and  in  a 
dozen  other  volumes,  that  further  instructions  would  seem  superfluous. 

Moreover,  the  instructions  given  have  been  so  maltreated  by  photographers 

as  to  discourage  further  suggestion. 

• 

179.  Colored  Collodion  for  Retouching  and  Improving  Negatives. — Orcanete,  or  red  col- 
lodion, when  poured  upon  the  back  of  the  negative,  lends  itself  very  rapidly  to  the 
manipulations  of  the  retoucher,  who  can  wholly  reduce  certain  limited  parts,  or  by  a 
regular  gradation  attenuate  its  non-actinic  coloration  as  his  good  taste  may  dictate.  Not 
only  can  feeble  or  strong  negatives  be  ameliorated,  but  even  good  portrait  negatives  can 
be  improved  by  diminishing  or  augmenting  the  effects  of  light  on  the  face,  or  by  render- 
ing details  more  perceptible  in  white  and  light-colored  clothes,  dresses,  hair,  etc. 

With  landscape  negatives  it  is  possible  to  give  better  relief  and  to  separate  the  different 
planes  of  the  pictures  one  from  another ,  to  bring  out  with  advantage  the  details  of 
foliage,  and  to  soften  the  over-strong  high-lights;  in  fact,  by  this  means  negatives  can 
be  considerably  modified,  and  yet  without  destroying  the  resemblance  or  rendering  the 
effect  unnatural.  Proofs  can  be  thus  printed  by  which  the  effects  and  the  different  colors 
of  nature  are  more  agreeably  interpreted. 

In  order  that  the  film  of  collodion  a  I'orcanete  may  be  rendered  more  resistant  during 
the  processes  of  decoloring,  recoloring,  and  scraping,  it  is  advisable  to  employ  a  pre- 
liminary coating  of  albumen  made  as  follows :  Take  the  albumen  of  three  eggs,  say  90 
c.  c.,  and  75  c.  c.  of  water,  well  beaten  together  into  a  stiff  froth;  and  add  50  c.  c.  of 
liquid  ammonia;  after  agitation  add,  a  little  at  a  time,  100  c.  c.  (3  fl.  ozs.  3  drs.)  of 
sulphuric  ether  and  50  c.  c.  (1  fl.  oz.  5  drs.)  of  alcohol  at  95°.  The  larger  the  quantity 
of  ammonia  added  the  greater  is  the  proportion  of  ether  and  alcohol  that  can  be  intro- 
duced without  coagulating  the  albumen.  The  ammonia,  ether,  and  alcohol  are  intended 
to  preserve  indefinitely  the  albumen,  to  render  its  application  to  glass  more  easy,  and 
also  to  hasten  the  desiccation.  When  the  above  mixture  is  freshly  made  and  allowed  to 
settle,  a  part  of  the  ether  separates  and  rises  to  the  surface ;  but  when  reshaken  it  again 
mixes,  and  after  some  days  the  ether  no  longer  separates  itself,  and  the  whole  may  be 
filtered  through  paper. 

The  back  of  the  negative  is  covered  either  by  means  of  a  soft  color  brush,  or  by  pour- 
ing it  on  like  collodion.  This  solution  of  albumen  when  wet  does  not  attract  small 
particles  of  dust  like  simple  albumen ;  and  it  dries  upon  a  draining-stand  in  from  ten  to 
twenty  minutes,  according  to  temperature. 

(435) 


436         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

There  is  a  disposition  however  to  return  to  "bottom  facts/'  or,  in  other 
words,  to  do  less  retouching  and  doctoring  and  to  endeavor  to  secure  a  better 

The  ethereal  tincture  of  orcanete  is  obtained  by  placing  in  a  wide-mouthed  bottle  the 
dry  roots  of  orcanete,  and  filling  nearly  up  with  sulphuric  ether  at  62°  or  65°.  It  must 
then  be  well  corked,  and  left  for  one  or  two  days  to  digest,  with  agitation  from  time  to 
time ;  finally  it  is  left  to  settle  for  twelve  hours,  and  may  then  be  filtered  through  paper 
into  a  smaller  bottle. 

The  alcoholic  tincture  is  produced  in  like  manner,  employing  alcohol  at  95°  instead 
of  ether. 

To  prepare  the  red  collodion,  take  filtered  ethereal  tincture  100  c.  c.  (3  fl.  ozs.  3  drs.), 
filtered  alcoholic  tincture  50  c.  c.  (1  fl.  oz.  5  drs.),  and  low-temperature  cotton  1^ 
grammes ;  it  is  scarcely  necessary  to  say  that  this  collodion  may  be  made  lighter  in  tint 
by  the  addition  of  plain  collodion.  It  is  very  handy  to  have  three  different  bottles,  one 
containing  a  lightly  tinted  solution,  the  second  a  darker  one,  and  the  third  a  saturated 
solution  of  orcanete.  Upon  the  dried  preliminary  film  of  albumen  the  red  collodion  is 
flowed  as  desired. — French  Photographer. 

Chemical  Retouching. — I  have  a  method  to  offer,  simple,  expeditious,  and  under  control, 
as  follows :  After  the  negative  is  fixed  and  washed,  flow  with  a  thick  solution  of  albumen, 
say — Albumen,  1  ounce ;  water,  4  ounces ;  and  dry.  When  dry,  coat  with  iodized  col- 
lodion, sensitize  in  the  bath ;  and  to  expose,  put  the  plate  in  the  dark  slide,  or  plate- 
holder  reversed,  the  film  uppermost.  Place  four  small  pieces  of  glass  at  each  corner,  and 
gently  lay  on  the  pieces  of  glass  a  plate  the  same  size  as  the  negative,  which  will  pre- 
serve the  sensitive  film  from  injury ;  close  the  door  and  expose  a  few  seconds,  by  drawing 
out  the  slide,  in  the  light.  It  will  be  understood,  of  course,  that  the  sensitive  film  is  on 
the  collodion  side  of  the  negative,  not  on  the  glass,  so  that  a  transparency  is  printed  in 
close  contact.  After  exposure,  develop  with  the  ordinary  developer,  wash,  fix,  dry, 
varnish,  and  the  whole  is  complete.  The  transparency  on  the  negative  will  not  need 
intensifying,  and  will  rarely  be  too  dense  by  the  application  of  the  developer  alone ;  the 
intensity,  however,  can  be  reduced  by  cyanide  of  potassium. 

Now  the  advantages  of  the  idea,  no  matter  how  carried  out,  are  manifold.  Freckles 
are  softened,  if  not  obliterated ;  scratches  and  pinholes  are  mollified,  if  not  "  stopped 
out ; "  "  heavy  blacks  "  are  toned  down,  and  shadows  softened ;  the  faintest  detail  in  the 
shadows  which  otherwise  would  be  lost  in  printing  is  increased,  preserved,  and  harmony 
pervades  the  whole  picture  instead  of  a  chalky,  freckly,  spotty,  undertimed  thing.  All 
undertimed  negatives,  or  those  with  heavy  shadows  and  dense  high-lights,  can  be  made, 
by  the  above  method,  to  yield  passable  prints ;  but  remember,  O,  courteous  reader,  that 
experience  must  be  acquired  ere  you  meet  with  unequivocal  success. — DAVID  DUXCAN. 

Obliterating  Opaque  Defects  in  Negatives. — Certain  negatives  are  rendered  apparently 
worthless  by  the  presence  of  numerous  opaque  spots  upon  the  surface. 

After  various  suggestions  respecting  the  reproduction  of  the  negatives  through  the 
instrumentality  of  transparencies,  upon  which  the  offending  spots  would  be  touched  out 
previous  to  making  use  of  them  for  forming  printing  negatives,  the  idea  occurred  to  us 
to  dissolve  the  spots  themselves  out  of  the  negative,  and  then  to  have  the  transparent 


RETOUCHING    AND    DOCTORING    THE    NEGATIVE.  437 

quality  of  negative  by  careful  manipulation  in  the  dark-room.  This  is  a 
cheerful  sign  and  warrants  me  in  confining  the  chapter  before  us  to  some 

holes  thus  made  properly  filled  by  pigment  of  the  same  density  and  color  as  the  portions 
immediately  surrounding. 

The  following  is  the  method  I  follow,  and  I  very  strongly  recommend  it  as  being  at 
once  simple,  expeditious,  and  certain :  Take  a  bit  of  caustic  potash  (there  is  no  necessity 
whatever  for  weighing  it,  a  piece  the  size  of  a  bean,  greater  or  less,  answering  quite  well) ; 
to  this  add  about  an  ounce  of  water,  and  when  it  has  dissolved,  which  will  be  the  case 
in  a  couple  of  minutes,  add  a  quantity  of  methylated  alcohol  equal  to  the  water  present. 
Now,  holding  the  negative  either  by  one  corner,  or,  as  we  prefer,  upon  a  pneumatic 
holder,  pour  this  solution  upon  the  surface,  taking  care  that  every  portion  is  covered. 
Allow  it  to  remain  on  for  about  half  a  minute,  pour  off  into  a  porcelain  or  glass  measure, 
and  again  apply  it  to  the  surface,  as  if  it  were  a  developing  solution.  Pouring  off  once 
more,  apply  to  the  surface  a  little  plain  water  with  alcohol,  and  follow  this  by  copious 
washing  with  water.  When  the  plate  is  dried  there  will  not  be  a  vestige  of  the  varnish 
found  on  its  surface. 

If  by  accident,  bad  varnish,  or  inadequate  temperature,  a  negative  has  been  damaged 
in  varnishing,  the  method  just  described  will  prove  a  most  effectual  means  of  denuding 
the  collodion  film  of  its  resinous,  pellicular  coating. 

By  means  of  the  treatment  described,  the  opaque  spots  upon  the  plate  are  rendered. in 
a  proper  condition  for  being  operated  upon  by  a  solvent.  The  solvent  I  use  is  a  some- 
what strong  solution  of  iodine  in  cyanide  of  potassium,  the  relative  proportions  being 
such  as  to  leave  the  solvent  salt  in  excess.  This  is  easily  effected  by  adding  iodine  until 
the  cyanide  solution  is  incapable  of  dissolving  more,  and  then  making  a  further  addition 
of  cyanide.  The  mechanical  conditions  are  secured  by  the  addition  of  a  few  drops  of 
mucilage  »of  gum  arabic. 

The  negative  having  been  placed  upon  the  retouching-desk,  and  a  tolerably  strong 
magnifier  utilized,  a  camePs-hair  brush,  charged  with  the  solution  described,  is  deftly 
applied  to  each  opaque  spot,  which,  after  a  few  seconds,  is  seen  to  become  quite  trans- 
parent. When  the  whole  of  the  spots  have  been  touched  in  this  manner,  a  gentle  stream 
of  water  is  applied  to  the  film,  so  as  to  clear  away  all  the  solution  of  iodine.  The  spots, 
previously  opaque,  but  now  transparent,  are  next  touched  in  by  means  of  an  appropriate 
pigment  to  be  selected  from  the  color-box,  a  mixture  of  burnt  sienna,  Prussian  blue,  and 
China  ink,  forming  a  pigment  which  answers  every  purpose. 

The  negatives  treated  in  this  manner  yield  points  which  do  not  demand  any  artistic 
operation,  and  in  which  it  is  almost  impossible  to  discover  any  fault  indicating  there 
having  been  at  one  time  something  seriously  amiss  with  the  negative. — W.  P.  BOLTON. 

Take  a  penknife  with  a  very  small,  pointed  blade,  sharpen  the  point  well,  and  with  it, 
using  a  magnifying  glass,  you  can  remove,  by  scraping,  small  opaque  spots  on  gelatine 
negatives,  when  dry.  You  can  also  modify  or  remove  an  objectionable  light  in  the  eye, 
or  any  little  defect  of  that  kind.  Your  first  trials  will  probably  be  failures,  but  practice 
will  show  you  the  proper  shape  of  blade  needed.  Of  course,  care  and  patience  are 
essential  to  success,  but  it  can  be  done. 


438         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

selected  notes  gathered  from  the  suggestions  of  practical  workers.     So  much 
for  general  work. 

Retouch  on  the  gelatine  film  by  grinding  with  resin,  fine  pumice-stone,  or  any  of  the 
methods  in  use ;  coat  with  plain  collodion,  and  when  dry  and  hard,  coat  with  good  var- 
nish ;  when  hard,  grind  again  carefully,  and  retouch  off  those  black  freckles  or  moles 
that  you  could  not  fill  up  on  the  first  film,  and  soften  those  heavy  lines  about  the  eyes 
and  mouth  that  would  not  "  yield  "  on  the  gelatine,  and  that  stray  lock  of  hair  that 
refused  to  "budge"  before  can  now  be  made  to  vanish.  Scan  the  whole  work  over,  and 
put  on  the  finishing  touches,  and  you  will  be  pleased  with  the  result. 

Clean  the  back  of  your  negatives  before  printing,  with  dry  pumice-stone  (powdered), 
using  the  ball  of  the  finger;  perhaps  a  knife  will  be  needed  to  scrape  the  largest  gelatine 
stains  or  spots  that  may  happen  to  be  there,  but  the  pumice-stone  will  make  them  shine 
and  print  clean. — F.  M.  ROOD. 

When  retouching  his  negatives  the  photographer  can,  if  he  has  the  genius,  do  almost 
anything,  so  that  he  has  shadow  enough  as  a  basis.  Here  he  becomes,  as  I  have  said, 
the  creator,  and  of  all  the  different  operations  of  a  negative,  this  is  the  portion  where  the 
artist  stands  out  most  prominently  and  proves  what  stuff  he  or  she  is  made  of.  There  is 
no  end  to  the  variety  of  work  one  may  introduce — grains  to  look  like  engravings,  hatch- 
ing, stippling,  brush  work.  It  is  not  enough  to  be  able  to  remove  spots  and  blemishes, 
or  soften  off  harsh  contrasts ;  girls  mostly  get  up  to  this  mark  of  excellence,  and  produce 
those  smooth,  meaningless,  pleasant  portraits  of  everyday  life.  The  retoucher  must  learn 
to  keep  an  expression  of  the  negative,  or  make  one  if  not  there,  and  this  is  the  lofty 
calling  of  a  true  retoucher.  He  must  put  a  soul  into  his  model,  else  he  cannot  call  him- 
self an  artist  any  more  than  the  painter  can  claim  the  title  who  only  daubs  potboilers. 
But  if  the  retoucher  can  do  this,  and  has  art  enough  in  himself  to  prefer  soul  to  beauty 
or  beautifying,  then  he  has  as  much  claim  to  call  himself  a  painter  or  an  artist  (if  he 
prefers  that  title)  as  any  R.  A.  in  the  clique  divine. 

Expression,  or  soul,  is  what  photographers  are  as  yet  deficient  in,  and  that  is  the 
province  of  the  retoucher.  I  want  to  see  a  photographer  rise  above  the  prejudice  of  the 
flattery-loving  public,  and  lead  them  by  intensity;  give  to  the  public  faces,  ugly  as 
Rembrandt's  portraits,  yet  pregnant  with  character.  I  want  to  see  seams,  and  wrinkles, 
and  warts,  as  the  Great  Creator  left  them — indexes  to  the  wearer's  character — and  not 
doll  faces,  which  simper  and  mean  nothing.  I  want  noses  in  all  their  varieties,  with 
their  own  individuality  intensified ;  cheek-bones  standing  out  as  they  may  be  in  the 
originals.  I  want  men  and  women  sent  down  to  posterity  as  they  are  and  not  as  they 
would  like  to  be ;  for  I  never  yet  saw  a  face  in  its  natural  state  that  I  could  call  ugly, 
although  I  have  seen  faces  by  rouge,  and  powder  cosmetiques,  and  false  eyebrows,  and 
also  by  the  retouching  which  they  were  themselves  so  delighted  about. 

Vice  and  crime  darken  the  souls  which  sit  behind  the  eyes — make  chins  hard,  and  lips 
thin  or  coarse — destroy  curves  which  are  upon  all  lips  when  innocent ;  yet  to  me,  the 
most  demoniac  face  that  ever  peered  out  upon  a  hunting  world  is  better  in  its  sombre 
gloom  than  that  same  face  smoothed  by  a  bad  or  mechanical  retoucher.  Beauty  is  ex- 
pression, not  chiselled  features.  A  baby  is  not  beautiful  until  it  can  notice  its  mother ; 


RETOUCHING    AND    DOCTORING    THE    NEGATIVE.  439 

Where  special  objects  are  to  be  attained,  special  resort  may  be  had  to  arti- 
ficial means.  Wisdom  and  care  should  always  be  exercised. 

then  the  meaningless  bit  of  flesh  is  lighted  up  with  a  ray  from  heaven.  That  God-beam 
the  photographer  must  catch ;  yet  it  is  not  a  smooth  surface,  but  a  light  breaking  through 
torn-up  cloud  mists. — HUME  NISBET. 

For  plain  photographic  work  I  advise  you  to  have  by  your  side  a  palette,  upon  which 
are  ground  moderate  portions  of  a  good  black  India-ink,  warm  sepia,  and  scarlet  lake. 
With  combinations  of  these  you  can  readily  imitate  the  photography  upon  which  you 
are  working,  whether  it  be  cold  or  warm  in  tone.  Of  course,  it  is  necessary  to  apply 
these  tints  with  a  brush ;  and  if  you  use  plain  water  as  a  dilutant,  you  will  leave  a  dead 
surface  that  betrays  your  trail.  Everyone  will  exclaim  :  Why  not  then  use  gum  water  ? 
that  will  leave  a  gloss.  Perfectly  right !  but  it  leaves  too  much  gloss.  In  addition,  I 
don't  believe  that  the  half  of  you  know  how  to  make  gum  water. 

Accept  my  formula,  and  adopt  it  or  no,  as  you  see  fit :  Picked  gum  arabic,  1  ounce  ; 
loaf  sugar,  1  drachm ;  acetic  acid,  30  minims ;  alcohol,  30  minims ;  water  in  sufiicient 
quantity,  say  from  six  to  eight  ounces. 

Do:i't  be  frightened  at  the  mention  of  the  acid,  and  at  the  idea  of  putting  a  modicum 
of  it  upon  the  surface  of  your  photograph.  Used  in  this  way  it  will  not,  I  assure  you, 
prove  destructive  in  the  slightest  degree. 

The  gum  water,  however,  I  do  not  use  for  the  indicated  purpose.  There  is  a  better 
vehicle — the  much-abused,  always  useful,  albumen. 

I  have  before  this  published  a  method  of  making  a  stock  albumen  that  is  equally  as 
serviceable  for  this  as  it  is  for  many  other  purposes.  It  is  not  original  with  myself,  but 
I  have  used  it  for  many  years,  and  have  come  to  consider  it  an  indispensability  in  a  studio 
or  gallery. 

Take  the  whites  of  eight  eggs,  carefully  separated  from  their  germs,  and  add  to  the 
mass  twenty-four  drops  of  glacial  acetic  acid,  diluted  with  one  ounce  of  water.  Stir  well 
for  a  minute  with  a  glass  rod,  making  no  attempt  to  beat  into  a  froth.  Let  the  liquid 
rest  for  at  least  an  hour,  and  then  strain  through  cambric  muslin,  Finally  add  half  a 
drachm  of  liq.  ammonia,  F.  F.  F.,  bottle,  cork  tightly,  and  use  as  required. 

Slightly  diluted  with  water,  nothing  can  excel  this  as  a  vehicle  for  water-color  painting 
upon  albumenized  paper.  Of  its  utility  for  the  preparation  of  negative  glasses,  for 
transparencies,  and  for  porcelain  work,  I  have  already  spoken 

If  you  cannot  touch  out  the  spots  neatly,  you  had  better  allow  them  to  remain.  On 
numberless  occasions  I  have  seen  prints  from  what  were  supposed  to  be  good  negatives, 
that  might  readily  have  passed  for  maps  of  the  heavenly  constellations.  They  were 
filled  with  white  spots,  crescents,  and  lines.  I  bave  frequently  asked  the  privilege  of 
inspecting  the  plates  from  which  they  were  made.  In  most  instances  the  printer  had 
endeavored  to  conceal  small  pinholes  or  light  scratches  with  that  very  useful  paint  of  my 
manufacture  (Opaque),  and  instead  of  having  a  scarcely  discernible  dark  speck  on  his 
paper,  caused  the  appearance  of  a  white  blot,  somewhat  difficult  to  eradicate.  To 
remove  these  transparent  imperfections  upon  the  negative,  you  must  possess  a  sharp  eye, 
a  steady  hand,  a  fine  brush  (Opaque,  of  course),  and  a  clear  comprehension  of  what  you 


440        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

A  neat  photographer  will  punctiliously  number  his  negatives,  and  when 
necessary  title  them.  An  engraving  diamond  is  a  convenient  tool  for  such 
work. 

are  doing.  Almost  invariably  when  I  have  washed  away  the  color  that  had  been  ap- 
plied, I  have  found  that  at  least  three  times  the  necessary  quantity  had  been  used. — 
JOHN  L.  GIHON. 

Many  a  valuable  negative  has  been  lost  because  no  system  adopted  by  the  photog- 
rapher has  existed  for  numbering  the  same.  The  engraving  diamond  (Fig.  341)  will 
prevent  loss  in  this  direction,  if  its  use  is  adopted.  It  is,  in  form  and  size,  something 
like  a  short  stylographic  pen,  and  consists  of  a  metal  handle  about  five  inches  long,  at 
the  end  of  which  a  diamond  is  permanently  set  for  the  purpose  of  writing  and  figuring 
upon  glass.  We  are  assured  by  the  manufacturer  that  it  will  even  write  on  steel. — 
GEORGE  MAY  POWELL. 

FIG.  341.  FIG  342. 


Below  are  some  hints  regarding  the  use  of  the  well-known  style  of  coffee-pot  shown  in 
Fig.  342,  as  a  varnish  pourer  and  as  a  means  of  separating  the  clear  varnish  from  the 
particles  of  dirt,  etc.,  apt  to  get  in  the  varnish  when  coating  plates.  The  engraving  will 
show  exactly  how  it  works.  A  piece  of  cotton  flannel  is  made  to  fit  into  the  inside  of 
the  top  portion,  and  on  that  some  filtering- cotton.  After  flowing  the  negative  the 
surplus  varnish  is  poured  back  into  the  top,  and  by  filtering  back  into  the  pot  we  have 
the  varnish  always  clean  and  nice.  The  bottom  of  the  part  marked  1  is  covered  with  a 
fine  wire  gauze,  They  can  be  obtained  at  any  kitchen  furnishing  store. — A.  MARSHALL. 

For  the  Production  of  Artificial  Negatives  by  Scratching  in  Lines  with  One  or  Several 
Needles. — Prepare  a  thin  negative  collodion,  containing  much  iodine,  which  is  as  usual 
poured  over  a  glass  plate  and  prepared  in  a  silver  bath.  After  having  taken  out  the 
plate,  and  cleansing  the  same  on  both  sides  with  water,  it  is  dried  and  laid  on  a  black 
cloth,  with  the  prepared  side  on  top. 

If  the  collodion  contained  much  iodine,  the  coating  will  appear  of  a  light-yellow  hue, 
which  in  this  case  is  just  the  thing  wanted. 

Now  make  several  instruments,  with  two  to  eight  needles  ranged  together  in  a 
straight  line,  with  sealing-wax,  with  which  a  drawing  can  be  scratched  in  the  yellow 


KETOUCHING    AND    DOCTORING    THE    NEGATIVE.  441 

The  varnishing  of  the  negative  should  not  be  neglected.  And  if,  for  any 
reason  the  varnish  must  be  removed,  extra  care  will  be  rewarded  by  the  best 
possible  success. 

layer  of  iodide  of  silver.     The  diagram  herewith  (Fig.  343)  represents  the  instrument,  a 
being  the  sealing-wax,  and  b  the  points  of  the  needles.    After  tracing  carefully  the 
outlines  of  a  drawing  upon  the  yellow  layer,  so  that  the  layer  does  not  get 
injured,  we  proceed  to  the  production  of  the  whole  drawing.     For  delicate 
details  only  an  instrument  of  two  to  three  needles  is  used ;  but  large  spaces 
are  rapidly  covered  with  an  instrument  of  many  needles.    Each  scratch  appears 
black,  as  the  yellow  layer  is  removed,  showing  the  black  sub-layer. 

The  picture  is  extremely  pleasing,  as  the  lines  run  beautifully  parallel,  and 
afford  many  very  delicate  gradations.  The  scratched-off  yellow  dust  must  be 
often  removed  with  a  broad  marten-brush.  When  the  drawing  is  finished, 
pour  on  the  plate  a  concentrated  solution  of  fuchsine  in  alcohol,  and  wash 
off  with  water.  The  fuchsine  colors  only  the  porous  collodion,  but  not  the 
clean  spots  of  the  glass,  and  renders  the  picture  more  opaque,  so  that  it  is  perfectly  suit- 
able for  heliographic  or  photo-lithographic  purposes. 

Finally  the  negative  must  be  varnished,  but  a  diluted  solution  of  gelatin  or  gum  arabic 
answers  better,  because  an  alcoholic  varnish  dissolves  the  fuchsine.  The  intensifying 
can  also  be  done  in  other  different  ways. — JOHN  L.  GIHON. 

To  Remove  Varnish  from  Negatives  or  Ferrotypes. — Use  saturated  solution  of  cyanide  of 
potassium,  one  part ;  alcohol,  95°,  two  parts ;  flow  on  and  off  as  in  redeveloping ;  will 
clear  of  varnish  very  rapidly,  so  the  negative  or  positive  can  be  washed  under  the  faucet, 
dried,  and  revarnished,  bright  and  fresh  as  new. 

I  discovered  this  method — partly  by  accident — some  months  ago,  and  have  used  it 
many  times  since,  always  successfully ;  and  having  never  heard  of  any  other  method  as 
good,  I  send  it  for  others  to  try. 

I  have  at  various  times  tried  most  of  the  published  methods  for  removing  varnish  from 
collodion  films — for  instance,  pure  alcohol  bath,  ammonia  and  alcohol,  common  crude 
potash  and  alcohol,  vapors  of  hot  alcohol,  etc. — all  more  or  less  available,  but  in  my 
experience  all  more  tedious,  more  expensive,  or  more  dangerous  to  such  films  than  this 
method. 

Whether  the  cyanogen  aids  the  solvent  action  of  the  potash  or  not,  the  materials  for 
this  combination  are  ready  in  almost  every  gallery,  and  seem  perfectly  reliable  in  action. 

Of  course,  it  must  not  be  used  on  negatives  strengthened  with  bichloride,  or  similar 
chemicals  especially  soluble  in  cyanide. — E.  K.  HOUGH. 


CHAPTEE   XYIII. 

FEINTING   ON   ALBUMEN   PAPER. 

180.  THE  printing  has  long  been  considered  the  most  mechanical  part  of 
pnotographic  work.     It  may  be  made  purely  so,  thereby  producing  all  grades 
and  qualities  of  pictures  according  to  conditions.     On  the  other  hand,  it  may 
be  made  as  productive  of  uniform  results,  as  any  department  of  photography. 

A  mere  mechanical  printer  will  handle  all  negatives  alike ;  the  weak,  the 
intense,  the  clean,  the  streaked,  all  are  printed  by  him  on  the  same  paper  and 
subjected  to  the  same  treatment.  His  results  show  as  many  varieties  and 
qualities  of  prints  as  there  are  varying  circumstances  of  light,  shade,  subject, 
chemicals,  etc.,  under  which  the  negatives  were  made.  The  prints  are  but  a 
reflex  of  all  these  uncontrollable  variations.  With  the  artistic  printer  this 
is  different.  He  expects  variety  in  negatives,  and  proceeds  accordingly.  He 
carefully  studies  their  qualities,  retouches  and  masks,  if  necessary ;  he  prepares 
his  paper  to  correspond  with  the  varying  conditions  of  the  negatives ;  he  prints 
from  each  negative  according  to  its  individuality ;  he  masks  one  part  of  the 
background,  and  prints  in  deeper  another  part,  as  may  be  required  to  give  the 
best  effect ;  he  tones  down  the  intense  lights  of  the  face  or  drapery,  by  exposing 
those  parts  while  the  rest  is  protected  ;  and  in  various  ways  controls  the  work 
as  it  progresses,  so  as  to  produce  the  best  possible  results.  Printing  in  this 
way  becomes  as  much  an  art  as  negative-making,  and  requires  as  much  study 
and  well-directed  skill  to  do  justice  to  the  work.  The  negative  manipulator 
should  well  understand  printing,  and  the  printer  should  be  a  good  dark-room 
manipulator. 

181.  Every  facility  should  be  given  the  printer.     He  should  have  abundance 

181.  Our  rooms  are  located  on  the  roof,  so  that  nothing  obstructs  the  light.  They  are 
fitted  with  plenty  of  shelf  and  cupboard  room.  I  will  give  separate  sketches  of  some  of 
the  most  important  conveniences. 

The  first  is  the  printing-room  table  for  changing  prints,  and  keeping  all  necessary 
articles  (Fig.  344).  It  is  9  feet  long;  40  inches  wide;  36  inches  high.  The  partition 
for  shutting  off  light  should  reach  nearly  to  the  top  of  the  room. 

Changing  Stand. — On  the  opposite  side  from  that  seen  in  the  cut  are  cupboards,  in 
which  all  printing-frames  are  kept,  when  not  in  use,  free  from  dirt. 
(442) 


PRINTING  ON  ALBUMEN  PAPER. 


443 


FIG.  344. 


/                                    \ 

m 

/ 

-  nnn 

MU/ 

of  light  all  the  day  long ;  from  the  south  if  possible ;  access  to  shade  in  case 
of  need ;  the  best  of  materials  and  a  convenient,  well-accoutred  work-room. 

Drawer  No.  1  is  for  albumen  paper,  fumed,  ready  to  print ;  in  the  upper  half  of  the 
drawer  is  a  shallow  tray  or  box  for  paper  after  it  is  cut  or  torn  ready  to  print.  No.  2. 
For  prints,  with  tray,  same  as  in  No.  1.  No. 
3.  Ground  glass  for  vignettes  ;  sticking  paper, 
cut  for  use;  printing  clips  or  clothes-pins; 
waste  strips  of  cardboard,  on  which  I  keep 
memoranda  and  printing-lists.  No.  4.  Vig- 
nette blocks,  all  sizes  and  shapes.  No.  5. 
Orange  and  tissue-paper  for  vignettes;  cut- 
outs of  all  sizes.  No.  6.  Cotton,  lead,  and 
sundries.  No.  7.  Large  basket  for  silver 
waste.  No.  8.  Large  printing-frames,  odds 
and  ends.  No.  9.  Shelf  for  odd  negatives, 
which  are  either  thrown  out,  or  carried  to  the 
negative-room,  once  a  month  or  so;  at  the 
left  end  I  keep  hammer,  tacks,  opaque,  paste, 
shears,  brush  for  dusting  negatives,  etc.  No. 
10.  All  negatives  ordered  from.  I  always  have  these  assorted  in  piles  according  to  the 
manner  in  which  they  are  to  be  printed,  vignette  or  otherwise.  No.  11.  On  this  shelf 
the  negatives  are  put,  when  the  order  is  printed,  and  from  here  they  are  taken  to  the 
negative-room  for  cataloguing.  These  shelves  are  on  a  partition  which  shuts  off  the 

strong  light  from  the  printing  window,  which 

FIG.  345.  would  otherwise  damage    paper  and    prints 

n  while  charging. 

Fig.   345  is  the  silver-bath   stand.     It  is 
28  x  24  x  33  inches  high.     I  keep  the  bath  in 
FIG.  346. 


the  tray  ready  tor  use  at  any  moment,  pouring  it  back  only  when  it  requires  fixing  over 
or  filtering.    By  lighting  the  gas  in  the  cupboard  below,  the  temperature  of  the  bath,  in 


444 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


Supplied  with  all  these  and  a  genuine  feeling  for  his  vocation  there  should  be 
no  drawback  to  his  production  of  the  best  prints. 

To  the  really  artistic  printer  his  art  becomes  an  intellectual  study  which 
develops  into  real  enjoyment. 

cold  weather,  can  be  raised  to  the  required  degree  in  a  few  minutes.  In  the  cupboard, 
all  bottles,  filters,  chemicals,  etc.,  used  for  the  bath  are  kept.  The  bath  is  kept  free  from 
dust  by  the  cover. 

Fig.  346  is  the  mounting-table.  It  is  7  feet  long,  3  feet  wide,  2  feet  5  inches  high. 
The  cut  gives  a  better  idea  of  this  useful  piece  of  furniture  than  any  explanation.  The 
large  cupboards  at  each  end  can  be  arranged  with  suitable  shelves,  and,  when  done, 
many  thousand  mounts  of  various  sizes  can  be  kept  therein — a  very  convenient  arrange- 
ment, preventing  loss  of  time. 

Fig.  347  shows  the  plan  of  the  north  end  of  the  mounting  room,  with  the  arrangement 
of  the  light  for  toning. 

Our  toning  window  faces  north,  and  we  have  a  light  board  which  just  fills  the  window. 
In  this  board  is  a  shutter  which  slides  to  the  left,  admitting  more  or  less  light,  as  required 
in  toning. 

Toning  and  washing  trays  are  kept  in  the  cupboard  beneath  the  toning  shelf  at  the  left. 


FIG.  347. 


FIG.  348. 


Shelf  No.  1,  Dry-plate  camera,  lenses,  and 
plate-holders;  No.  2,  toning  chemicals,  No. 
3,  carbon  materials;  No.  4,  glass  cut-outs, 
Robinson  trimmers,  forms,  etc. 

Fig.  348  is  of  a  sectional  view  of  the  printing-room  window,  and  end  view  of  the 
changing  table. 

The  large  amount  of  cupboard  and  drawer  room  which  we  have,  is  considered  of  great 
importance,  inasmuch  as  all  the  manipulations  are  conducted  with  freedom  from  dust 
and  dirt,  enemies  which  injure  and  destroy  so  much  work  that  would  otherwise  be  good. 
The  rooms  are  painted  a  chocolate-brown,  a  pleasing,  subdued  color,  and  one  from  which 
no  disagreeable  reflected  light  from  the  printing  window  can  come.  A  speaking-tube  and 
an  elevator  for  carrying  negatives  back  and  forth  connect  with  the  rooms  below,  saving 
much  time  and  many  steps. — HOWARD  A.  KIMBALL. 


PRINTING    ON    ALBUMEN    PAPER.  445 

There  is  nothing  in  science  or  art  more  beautiful,  except  always  the  devel- 
opment of  a  latent  image,  than  the  coming  up  from  the  pure  white  sheet  of 
paper  of  the  positive  print. 

182.  The  theory  of  silver  printing  can  be  very  concisely  stated  as  follows  : 
When  nitrate  of  silver  is  brought  in  contact  with  an  organic  substance,  the 

resulting  compound  is  found  to  be  affected  by  light  in  a  somewhat  peculiar 
way :  the  compound  slowly  darkens  to  a  reddish  tint ;  the  exact  chemical 
reaction  that  takes  place  is  very  complex  to  trace,  but  it  may  be  accepted  that  an 
oxide  of  the  organic  matter  and  silver  is  formed.  This  oxide  is  stable,  unlike 
the  suboxide  of  silver,  and  is  not  acted  on  by  fixing  agents  to  any  great  extent. 

183.  The  most  important  of  the  organic  substances  used  in  printing  is  albu- 

182.  The  negative  having  been  obtained,  the  next  step  is  to  produce  positives  from  it. 
The  fact  long  known  to  man,  that  nitrate  of  silver  in  the  presence  of  organic  matter, 
darkens  in  sunlight,  is  utilized  for  this  purpose.     In  darkening,  it  is  probably  reduced 
to  a  subnitrate,  but  why  it  should  be  reduced,  and  why  in  the  presence  of  organic  matter, 
is  a  question  that  will  not  be  proposed  here,  because  its  answer  would  lead  so  far  into  the 
fields  of  theoretical  chemistry  that  we  might  find  ourselves  more  in  shadow  than  before 
we  entered  those  domains.     The  fact  is  certain,  that  the  nitrate  does  darken  when  exposed 
to  the  sun,  and  it  is  also  true  that  this  fact  is  utilized  in  obtaining  positive  prints.    The 
paper  is  first  albumenized,  because  it  gives  a  fine,  smooth  finish  to  it,  and  allows  it  at 
least  to  work  as  fast  as  the  plain  paper.     When  this  is  floated  upon  a  nitrate  of  silver 
bath,  albuminate  of  silver  is  formed ;  but  as  there  is  also  free  nitrate  of  silver  present, 
and  as  it  is  a  so  much  simpler  salt,  and  as  the  reactions  are  similar,  we  will  consider  it 
as  nitrate  of  silver,  in  the  presence  of  organic  matter — albumen.     A  piece  of  paper  is 
then  taken,  with  a  coating  of  albumen,  and  coated  with  nitrate  of  silver  and  allowed  to 
dry.     If  now  this  is  used  to  print  with,  it  would  be  found  that  the  reaction  would  be 
retarded  by  the  nitric  acid  that  would  be  set  free  (nitric  acid  being  liberated  in  this  case 
in  the  same  way  that  we  have  seen  chlorine,  bromine,  and  iodine  liberated  before). 
Something  is  evidently  needed  to  seize  upon  the  escaping  nitric  acid,  and  by  uniting 
with  it  prevent  it  from  doing  any  damage.    This  "  consummation  devoutly  to  be  wished" 
is  obtained  by  the  "  fuming/'  when  the  sensitized  papers  are  hung  up  in  a  box  and  sub- 
jected to  the  fumes  of  ammonia.     Those  fumes,  acting  upon  the  nitrate  of  silver  on  the 
paper,  form  with  it  ammonio-nitrate  of  silver.    So,  then,  when  the  paper  is  placed  under 
the  negative,  and  the  light  acts  upon  it,  and  in  acting  upon  it  disengages  nitric  acid,  this 
nitric  acid  instead  of  escaping,  instead  of  retarding  the  action  of  the  light,  seizes  upon 
the  ammonia,  forms  nitrate  of  ammonia,  and  then  as  a  retarding  agent  its  work  is  at  an 
end.     The  sensitized  paper  having  been  exposed  for  a  sufficient  time  is,  as  everyone 
knows,  taken  from  the  printing-frame  and  washed  in  water — washed  so  as  to  remove  the 
free  nitrate  of  silver ;  after  being  washed  in  several  changes  of  water  it  is  transferred  to 
the  toning  bath. — HENRY  M.  M'LsriRE,  M.  E. 

183.  All  paper,  but  especially  albumenized  paper,  is  stored  in  an  unheated  room,  so 
that  it  may  not  become  dry  and  brittle,  but  always  remain  soft  and  supple.     In  the  heat 


446         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

men.  It  has  been  used  hitherto  in  preference  to  any  other  organic  compound, 
on  account  of  the  delicate  film  it  forms  on  the  paper,  free  from  all  roughness, 
and  also  on  account  of  the  beautiful  color  the  print  takes  by  the  production  of 
the  albumiuate  of  silver.  The  albumen  should  be  used  fresh,  and  in  a  slightly 
alkaline  condition.  The  principal  commercial  objection  to  its  employment  in 
.such  a  condition  as  the  foundation  of  the  picture,  arises  from  the  difficulty  that 
is  experienced  in  coating  the  paper  evenly  with  it.  Makers  of  paper  prefer  old 
albumen,  which  gives  a  slightly  acid  reaction.  When  in  this  last  condition, 

of  summer,  when  it  might  be  too  hard  and  brittle,  I  take  it  some  hours  before  silvering 
it,  or  the  night  before,  and  place  it  in  the  damp-room  so  that  it  may  attract  a  little 
moisture,  as  nothing  is  more  perverse  than  paper  that  will  not  lie  flat  upon  the  bath,  but 
always  rolls  up — except,  perhaps,  when  air-bubbles  make  their  appearance.  This  dry 
paper  also  does  not  take  on  the  silver  so  equally  as  that  which  contains  a  certain  quantity 
of  moisture ;  and,  in  fact,  the  whole  process  goes  much  more  smoothly  with  the  latter 
sort.  I  now  place  my  sheet  upon  the  bath  and  let  it  float,  with  a  gentle  movement,  for 
a  minute  and  a  half  or  two  minutes.  In  order  to  produce  the  same  result,  the  time  of 
floating  should  be  the  same  for  all  the  sheets.  At  the  end  of  that  time  I  draw  each  sheet 
slowly  out  of  the  bath  and  place  it,  wet  side  lowermost,  upon  a  sheet  of  chemically  clean 
blotting-paper,  placing  above  it  a  sheet  of  strong,  smooth,  packing-paper,  and  with  the 
palms  of  my  hands  I  smooth  it  out  in  all  directions,  giving  the  pressure,  which,  having 
the  sheet  between  my  hands  and  it,  it  can  now  bear,  so  that  all  the  moisture  may  be 
sucked  up  by  the  sheet  of  blotting-paper  below  it.  Of  course,  the  table  upon  which  the 
three  layers  of  paper  are  laid  ought  to  be  perfectly  flat.  The  paper  may  be  rubbed  until 
it  is  almost  dry,  and  then  laid  aside  at  once,  but  that  is  not  necessary,  as  without  it,  by 
the  time  I  come  to  the  fourth  sheet  the  first  will  be  ready  for  use. 

There  is  really  not  much  silver  absorbed  by  the  blotting-paper,  since  what  it  does 
suck  up  is  merely  the  solution  that  would  otherwise  run  off,  and  which  contains  but 
little  silver;  so  that  really  there  is  none  lost  if,  when  the  blotting-paper  can  be  used  no 
longer,  it  be  reduced  to  ashes  in  order  to  recover  the  silver. 

Besides  the  comfort  of  being  able  to  prepare  a  great  quantity  at  a  time,  and  to  expose 
it  soon  after,  this  way  of  preparing  paper  possesses  the  advantage  over  the  other  that, 
owing  to  the  quick  drying,  the  sensitive  film  is  entirely  on  the  upper  surface,  and  cannot 
sink  into  the  substance  of  the  paper  itself.  The  print  is,  therefore,  more  upon  the  upper 
surface,  and  is  consequently  softer  and  more  brilliant,  and  considerably  more  easily  fixed. 
A  very  weak  soda  bath  can  then  be  used,  five  per  cent,  of  the  salt  being  sufficient,  and  a 
very  small  addition  of  bicarbonate  of  soda  has  a  favorable  effect  on  the  whites. — F.  W. 
GELDMACHER. 

Cutting  the  Paper. — The  following  methods  are  most  extensively  used : 

Fold  the  paper  into  halves  lengthwise,  then  into  thirds  crosswise,  making  six  4x4 
pieces,  which  folded  again  lengthwise  will  make  twelve  cabinets,  which  stretch  in  the 
width,  or  four  panels  and  eight  cabinets. 

Folding  the  sheet  into  halves  crosswise  you  will  obtain  two  11  x  14  pieces,  which 


PRINTING    ON    ALBUMEN    PAPER.  447 

the  paper  is  easily  coated,  though  the  toning  is  retarded,  and  inferior  pictures 
are  the  result. 

There  are  two  kinds  of  paper  used  principally  for  albumeniziug  :  Rives  and 
Saxe.  They  are  both  starch-sized  papers. 

184.  The  "sensitizing  bath"  has  been  a  subject  of  dire  tribulation  among 

folded  again  will  make  four  8x10;  these  folded  again  will  make  eight  boudoirs ;  when 
folded  again  sixteen  cabinets  will  be  obtained,  all  stretching  in  the  width.  If  cards  are 
wanted,  each  cabinet  will  make  two  cards  when  doubled,  thus  getting  thirty-two  cards 
out  of  a  sheet,  all  stretching  up  and  down. 

Fold  a  sheet  of  paper  in  length  three  times  and  fold  each  strip  five  times,  thus  getting 
fifteen  cabinets  stretching  up  and  down. 

Detach  a  strip  off  the  sheet  six  and  a  half  inches  wide,  which  doubled  twice  will  make 
four  cabinets  or  four  panels.  The  remainder  of  the  sheet  will  make  eight  cabinets  or 
four  cabinets  and  four  panels.  For  cabinets  fold  the  paper  evenly,  then  turn  it  half 
around,  and  double  turn  again  and  double.  This  gives  you  eight  cabinets.  All  the 
above  pieces  will  stretch  the  same  way.  If  you  want  to  make  panels  and  cabinets  cut 
as  follows :  Place  the  end  of  the  piece  next  to  you,  fold  over  so  as  to  make  one  strip  six 
and  a  half  and  the  other  seven  and  a  half  inches  wide,  now  turn  and  fold  as  you  did  for 
cabinets. 

All  pieces  of  the  last-described  method  will  stretch  alike  in  the  width.  Photographers 
having  German  customers,  as  a  general  rule,  cut  their  paper  to  stretch  in  the  length,  as 
the  Germans  principally  have  round  faces,  while  American  faces  are  usually  lacking  in 
width. — CHARLES  KRAUSS. 

184.  Having  been  bothered  with  albumen  paper  curling  up  when  silvering,  and  many 
times  becoming  dizzy  by  constant  breathing  on  the  back  of  the  paper,  to  keep  it  down,  I 
contrived  a  device  to  obviate  this  trouble.  I  will  explain : 

Have  a  box  made  of  half  inch  stuff  (pine),  25  inches  long,  19  inches  wide,  and  6  inches 
high  inside  (if  measured  from  outside,  half  an  inch  larger  every  way) ;  then  have  the 
box  sawed  so  as  to  make  the  cover  two  inches  high,  leaving  the  main  box  four  inches 
high  inside  (Fig.  349).  Put  a  handle  on  each  end  of  the  box,  and  on  top  of  the  cover, 
in  the  centre.  Have  this  box — cover  and  all — lined  inside  with  zinc,  and  let  the  zinc 
extend  above  the  top  of  the  box  all  round,  so 

that  when  the  cover  is  on  it  will  fit  tight,  FIG.  349. 

and  make  it  air-tight,  or  nearly  so.  Then 
have  a  pan  made  out  of  galvanized  iron,  20 
inches  long,  14  inches  wide,  and  3  inches 
deep,  with  a  piece  of  stiff  wire  around  the  top, 
to  make  it  substantial — the  same  as  any  ordi- 
nary pan.  Have  a  wire  handle  on  each  end 
of  this  pan ;  also  a  leg  not  quite  an  inch  high, 

under  each  corner.  Now  put  water  in  the  box,  so  that  the  pan,  when  it  has  albumen 
paper  in  it,  does  not  float.  I  then  cut  the  sheets  of  albumen  paper  in  half,  as  I  only  silver 


448 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY 


inexperienced  photographers,  or  those  who  seem  unwilling  or  incapacitated  to 
receive  instruction.  The  subjoined  formula  is  recommended  :  Silver  solution, 
35  grains  strong,  J  gallon  ;  muriatic  acid,  J  ounce.  Shake  well,  and  add 
enough  ammonia  to  make  it  slightly  alkaline ;  shake  well,  filter.  The  filter 
may  be  used  over  and  over  again.  Every  time  you  strengthen,  add  a  little 
acid  and  ammonia.  Add  a  little  C.  P.  nitric  acid  when  red  tear-drops  appear. 
Fume  with  strong  ammonia  eight  or  ten  minutes. 

half  a  sheet  at  once,  and  trim  off  the  ends  that  have  no  albumen  on,  and  put  from  two  to 
three  dozen  sheets  in  the  pan — albumen  side  down,  after  first  placing  a  piece  of  clean 
blotting  paper  on  the  bottom  of  the  pan  ;  put  on  the  cover  of  the  box,  and  let  it  remain  for 
forty-eight  hours.  The  paper  is  then  in  splendid  condition  for  silvering.  The  way  I  do 
is  to  take  off  the  cover,  and  carry  the  pan  (paper  and  all)  to  where  I  want  to  silver;  have 
about  two  thicknesses  of  blotting  paper,  which  place  on  top  of  all  the  paper  whilst  you 
are  silvering  a  piece ;  this  keeps  the  back  of  the  paper  from  drying.  I  leave  these  blot- 
ters now  on  the  albumen  paper  all  the  time,  after  the  paper  seems  to  be  moist  enough. 
The  blotters  seem  to  absorb  the  moisture  that  would  otherwise  fall  to  the  paper.  You 
can  regulate  it  now  to  suit  yourself.  When  through  silvering,  carry  the  pan  back  and 
put  it  in  the  box  again,  and  shut  it  up.  The  next  time  you  want  to  silver,  whether  it  is 
a  day  or  a  week,  you  will  find  the  paper  in  splendid  condition. — Gr.  W.  WISE. 

A  great  many  good  negatives  are  ruined  after  considerable  use  by  scratches  from  the 
finger  nails  when  removing  prints  from  the  pressure-frames,  and  from  the  ragged,  horny 
edges  of  the  albumen-paper  as  it  passes  over  them. 

I  have  adopted  a  plan  which  entirely  prevents  injury  to  the  negative  from  the  latter 
cause.  Fig.  350  illustrates  this.  A  is  a  strip  of  steel,  the  upper  edge  very  smoothly 

ground,  fastened  firmly  in  the  block  It,  and  to 
the  table  D,  by  means  of  the  hand-clamp  (7. 
This  strip  may  be,  say,  a  foot  long.  The  sensi- 
tized paper  is  cut  to  size  for  use,  and  then 
drawn,  plain  side  down,  from  end  to  end  over 
the  steel  edge,  holding  it  in  the  same  manner 
(i.  e.,  by  each  end)  as  you  would  when  ironing 
a  ribbon  over  a  stove-pipe.  In  this  manner 
all  the  rough,  ragged  edges  are  removed,  and 
rendered  perfectly  harmless.  This  idea  is  worth 
hundreds  of  dollars  in  saving  valuable  nega- 
tives. 

The  little  hand  screw  clamp,  C,  is  a  valuable 
little  thing,  too.  It  is  easily  made,  and  will 
answer  for  any  machine,  such  as  the  card-cutter, 
press,  steel  strip,  and  so  on ;  for  any  of  these 
may  be  screwed  to  the  clamp,  the  clamp  to  any  table  or  bench,  and  any  or  all  quickly 
removed  if  the  space  they  occupy  be  needed.— B.  W.  KILBURN. 


FIG.  350. 


PRINTING    ON    ALBUMEN    PAPER. 


449 


The  method  of  floating  the  paper  surely  needs  no  particular  description.  It 
is  by  no  means  imperative  that  a  certain  corner  should  be  first  approached  to 
the  solution.  The  photographer  soon  acquires  peculiarities  of  manipulation 
that  enable  him  to  do  his  work  better  and  with  more  satisfaction  to  himself, 
than  if  he  followed  a  prescribed  rule.  There  is  one  general  principle  to  be 
observed.  It  is,  that  if  the  negatives  are  very  hard  the  strength  of  the  silver 
solution  can  be  lessened,  and  if  they  are- weak,  it  should  be  much  increased. 

This  sketch  will  serve  to  explain  the  arrangement  of  the  table  when  silvering  paper 
(Fig.  351).  A,  the  frame,  with  corks  glued  on  the  wooden  rod  nine  inches  apart,  upon 
which  I  have  placed  one  piece  of  paper ;  under  it  a  glass  to  catch  ths  drops  of  silver.  B 
is  a  glass  dish.  C  is  a  paper  cut  and  ready  for  silvering.  D  is  a  pin-cushion. 

Now  let  me  try  to  explain  just  how  to  silver  a  piece  of  paper.  First  I  will  sketch  a 
sheet  of  paper  as  it  lays  before  us  face  down,  and  mark  it  with  letters  in  each  corner 

(Fig.  352).     Bend  up  a  small  corner  at  D  at 

^rG-  3^1.  right  angles  to  face,  so  as  to  better  take  hold  of 

it  in  removing  it  from  the  silver,  and  so  that 
this  little  corner  may  be  kept  dry,  through  which 
to  stick  the  pin. 

Now  take  hold  of  paper  with  left  hand  at 
corner  A,  and  with  right  hand  at  corner  D; 
keep  left  very  low  and  right  very  high  as  you 
place  it  on  the  silver,  so  that  the  bend  in  paper 

FIG.  352. 


may  be  as  close  to  corner  A  as  possible ;  let  this  rounding  or  bent  part  first  touch  the 
solution ;  keep  the  finger  holding  the  paper  at  A  as  near  the  solution  as  you  can  without 
touching,  and  hold  well  over  to  left  side  of  dish,  lowering  slowly  and  steadily  the  right 
hand ;  thus  the  contact  of  the  paper  will  be  diagonally  across  the  sheet,  and  will  expel 
to  right  side  of  dish  all  bubbles  that  may  incline  to  form. 

Bubbles,  if  formed  at  all,  will  most  likely  be  at  first  point  of  contact  close  to  A. 
Carefully  lift  at  A  with  small  glass  rod,  and  remove  any  that  may  appear,  lifting  the 
paper  half  its  length  from  this  end  for  examination,  and  immediately  do  the  same  at 
Z>end. 

After  the  paper  has  lain  for  from  one  to  one  and  a  half  minutes,  lift  it  at  corner  D  by  the 
bent-up  portion  with  left  hand  stick  a  pin  through  it,  and  raise  slowly  and  steadily  from 

29 


450 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


185.  After  removal  from  the  silver  solution,  the  paper  is  allowed  to  become 
thoroughly  dry,  and  is  subjected  to  the  fumes  of  strong  ammonia.     It  is  then 
ready,  when  cut  into  the  required  sizes,  to  be  placed  in  contact  with  negatives 
in  printing  frames. 

The  print  should  have  the  highest  lights  nearly  white,  and  the  shadows 
verging  on  a  bronzed  color,  before  toning. 

There  are  a  great  many  defects  which  should  be  carefully  observed  and  pre- 
vented or  cured. 

186.  Small  white  spots,  with  a  black  central  pin-point,  are  often  met  with 
in  prints.     Dust  on  the  paper,  during  sensitizing,  will  cause  them,  the  dirt 
forming  a  nucleus  for  a  minute  bubble.    All  paper  should  be  thoroughly  dusted 
before  being  floated  on  the  sensitizing  bath. 

Gray,  star-like  spots,  arise  from  small  particles  of  inorganic  matter,  such  as 
oxide  of  iron,  lime,  etc.,  which  are  present  in  the  paper.  They  become  appar- 
ent by  decomposition  during  the  printing  operations.  They  may  generally  be 
discernible  by  examining  the  paper  by  transmitted  light. 

the  solution  to  wooden  rod,  where  you  will  fasten  it  upon  the  first  cork,  albumen  side 
out.  After  all  four  corks  are  filled,  proceed  to  remove  paper  from  cork  one  to  dark-room 
for  drying. — CHAS.  WAGER  HULL. 

185.  I  inclose  you  a  rough  sketch  and  short  description  of  a  paper-drying  apparatus 
that  I  use  (Fig.  353).  It  consists  of  a  common  flour  barrel  with  a  sheet-iron  head  in  the 
bottom  and  the  top  open,  covered  with  a  lid  about  one  inch  thick  and 
two  or  three  inches  larger  than  the  top  of  the  barrel.  To  the  under  lid 
is  a  frame  almost  as  long  as  the  barrel ;  the  paper  is  fastened  to  this 
frame,  and  then  let  down  into  the  barrel.  The  under  side  of  the  cover 
has  some  thick  cloth  tacked  around  it,  so  that  it  serves  to  keep  the  heat 
in  the  barrel  by  packing  the  joint.  A  common  coal-oil  lamp  is  used 
under  it  for  heat. — A.  E.  TURNBULL. 

186.  It  sometimes  happens  that  the  paper  prints  are  rea  even  after 
very  strong  fuming.  Why  ?  By  the  action  of  light  the  chloride  of 
silver  is  reduced  to  a  subchloride,  evolving  chlorine,  and  if  the  paper 
be  damp  the  chlorine  is  taken  up  by  the  water  in  the  paper  probably 
as  hydrochloric  acid,  and  reddens  the  paper  just  the  same  as  it  would 
redden  litmus  paper,  and  also  serves  in  a  measure  to  assist  the  printing. 
The  remedy  is  easy ;  dry  the  paper  and  the  pad  just  before  placing  it 
upon  the  negative.  An  oil  or  gas  stove  should  be  kept  handy  for  that 
purpose,  but  care  should  be  exercised  not  to  dry  the  paper  too  much, 
as  some  little  moisture  seems  also  to  facilitate  the  reduction  of  the 
chloride  of  silver.  Very  dry  paper  is  also  both  brittle  and  disagreeable  to  handle.  I 
have  seen  prints  come  out  weak  from  excessive  dryness  of  the  paper  when  it  was  fully 


FIG.  353. 


PRINTING    ON    ALBUMEN    PAPER.  451 

Bronzed  lines  (straight)  occur  through  a  stoppage  during  the  floating  of  the 
paper  on  the  sensitizing  solution.  Should  the  lines  be  irregular,  forming  angles 
and  curves,  it  is  probable  that  a  scum  of  oxide  of  silver,  etc.,  may  be  detected 
on  the  surface  of  the  sensitizing  solution.  A  strip  of  blotting-paper  drawn 
across  will  remove  the  cause  of  the  defect. 

Should  the  print  appear  marbled,  it  may  be  surmised  that  the  sensitizing 
solution  is  weak,  or  that  the  paper  has  not  been  floated  long  enough.  In  some 
cases  it  may  arise  from  imperfect  albumenizing,  but,  in  ordinary  commercial 
samples,  the  cause  can  be  easily  traced. 

After  printing  the  toning  follows. 

silvered.  Having  produced  a  rich  print  with  clear  high-lights  and  deep,  slightly  bronzed 
shadows,  it  ought  to  tone  up  rich  and  strong,  and  if  it  does  not  do  so  the  error  was  surely 
'after  the  printing ;  look  for  the  failure  close  to  the  point  where  failure  first  revealed 
itself.— F.  M.  SPENCER. 

187.  A  solution  of  chloride  of  gold.  What  can  this  do  ?  Gold  is  what  might  be  called 
an  ascetic  metal ;  it  likes  to  live  alone.  In  other  words,  it  is  easily  reduced  from  its  salts 
to  the  metallic  state.  So  when  this  sheet  of  paper,  covered  all  over  with  silver  salts,  is 
brought  into  a  solution  of  chloride  of  gold,  the  silver,  having  a  great  attraction  naturally 
for  chlorine,  and  the  gold  parting  willingly  with  its  chlorine,  it  is  no  more  than  can  be 
expected  to  find  the  chlorine  leaving  the  gold  and  uniting  with  the  silver,  forming,  of 
course,  chloride  of  silver — the  dark  subchloride,  when  the  silver  has  been  reduced  to  the 
subchloride  by  the  action  of  the  light,  and  the  white  chloride  when  the  silver  is  un- 
altered, and  then  the  gold,  having  lost  that  which  held  it  in  solution,  has  nothing  to  do 
but  come  down  as  a  precipitate  of  metallic  gold,  and  so  metallic  gold  is  deposited  upon 
the  picture.  It  is  noticed  that  the  toning  bath  has  a  lowering  effect  upon  the  picture ; 
and  also  that  if  it  be  alkaline,  this  effect  is  reduced  to  a  great  extent,  so  for  this  reason 
alkaline  toning  baths  are  often  used.  There  can,  however,  be  three  kinds  of  toning 
baths  evidently :  acid,  neutral,  and  alkaline.  An  acid  solution  will  tone  brownish,  a 
neutral  violet,  and  an  alkaline  bluish  violet.— HENRY  M.  M'!NTIRE,  M.  E. 

Toning -bath. — No.  1.  Stock  solution.  Take  a  quart  bottle,  in  which  you  keep  a  thor- 
oughly saturated  solution  of  sal  soda  as  stock  solution.  Place  two  ounces  of  this  stock 
solution  in  an  eight-ounce  bottle,  and  fill  with  water. 

No.  2.  Take  a  half-pound  bottle,  in  which  you  dissolve  15  grains  of  chloride  of  gold 
in  15  ounces  of  water. 

No.  3.  Toning-bath.  Take  about  a  half-gallon  of  lukewarm  water,  add  a  small  tea- 
spoonful  of  salt  and  two  ounces  of  gold  solution,  then  test  it ;  the  litmus  paper  should 
turn  red ;  to  this  add  enough  sal  soda  to  turn  the  same  piece  of  litmus  paper  blue  again  ; 
very  little  is  required — two  teaspoonfuls  will,  as  a  general  rule,  suffice.  Be  sure  and 
measure  everything,  especially  the  sal  soda,  because,  if  too  much  is  used,  the  prints  will 
not  tone,  but  bleach. 

With  this  toning-bath  you  can  get  any  desired  tone  with  very  little  effort.  The  prints 
will  tone  in  about  twelve  minutes.  The  prints  should  be  toned  blue  on  surface,  as  they 


45*2        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

187.  The  object  of  "toning"  a  print  is  to  change  the  reduced  silver  to  a 
sightly  color  that  will  not  be  destroyed  after  it  has  been  immersed  in  the  fixing- 
bath.  The  action  of  toning  may  be  considered  somewhat  analogous  to  that  of 
intensifying  the  negative,  by  change  of  color ;  the  reduction  of  metallic  gold 
from  the  chlorine  on  certain  portions  of  the  print,  being  similar  to  that  of  the 
metallic  silver  from  the  nitrate.  The  position  of  the  portion  of  the  picture  on 
which  it  is  thrown  down  is  determined  by  the  position  of  the  reduced  silver  on 
the  paper.  Where  there  is  metallic  silver,  there  the  metallic  gold  is  thrown 

will  go  back  a  little  in  the  hypo;  by  doing  so,  you  will  get  as  rich  a  tone  as  can  be  pro- 
duced by  any  bath  in  use.  The  vignettes  are  toned  separate  to  secure  uniform  tones  in 
them.  The  large  prints  are  always  toned  first,  to  keep  them  safe  from  tearing  and 
breaking  the  albumen  surface  by  too  much  handling. 

Both  baths  can  be  used  over,  but  are  generally  made  new  every  day,  the  gold  being 
pretty  well  used  up  by  the  last  batch  of  prints. 

Waste  toning-baths  should  be  kept  in  a  large  crock,  throwing  the  gold  down  with 
bicarbonate  of  soda  or  protosulphate  of  iron. — CHARLES  KRAUSS. 

Why  do  different  portions  of  a  sheet  of  paper,  silvered  intact,  tone  so  differently? 
I  would  venture  the  following  explanation:  If  a  printer  notices  carefully  his  paper  as 
received  from  the  dealer,  he  will  observe  a  diagonal  line  of  slightly  crumpled  appearance 
running  from  corner  to  corner.  This  is  produced  by  the  line  or  stick  over  which  the 
paper  is  hung  to  dry  when  albumenized,  and  is  the  line  of  unequal  tones,  as  it  might  be 
called. 

After  silvering,  there  is  to  be  seen,  though  very  faintly,  other  lines  running  at  right 
angles  with  the  first  toward  the  corners  of  the  sheet,  and  forming,  when  the  sheet  is 
spread  flat,  the  appearance  as  shown  in  Fig.  354. 

As  before  stated,  these  small  lines  are  very  faint  and  hardly  discernible  before  printing ; 

but  put  a  piece  under  a  negative  having  heavy  shadows  and  a  great  deal  of  clear  glass, 

and,  lo !  you  have  a  map  of  rivulets  and  streams  of  all  sorts 

FIQ-  354. running  parallel  to  each  other,  rising  in  the  centre  line  and 

losing  themselves  as  they  come  to  the  edge. 

These  last  lines  are  caused  by  the  albumen  running  toward 
the  corners  as  the  sheet  hangs  to  dry,  forming  a  regular  drain- 
age from  the  centre  toward  the  edge.  Whether  this  results 
from  the  condition  of  the  albumen,  or  from  some  adulteration 
of  it,  I  am  not  certain,  but  it  seems  to  disintegrate  (if  I  may  be 
allowed  the  use  of  the  word  in  speaking  of  a  liquid),  it  loses  its 
homogeneous  state,  and  seems  to  separate  like  curds  and  whey, 
robbing  the  centre  of  the  sheet,  and  building  up  the  edges. 

Such  paper  is  poor  at  its  best  estate,  but  the  centre  is  remark- 
ably so,  and  as  the  print  made  on  it  goes  to  the  toning-bath  its 

poor  qualities  become  more  apparent  at  every  stage  till  they  reach  the  culmination  of 
"cussedness"  under  the  action  of  the  gold  salts,  when,  before  the  other  parts  of  the  same 


PRINTING    ON    ALBUMEN    PAPER.  453 

down.  The  process  might  be  almost  called  "electro-gilding."  The  terchloride 
of  gold,  or  a  double  salt  of  the  terchloride  «f  gold  and  potassium  or  sodium, 
is  invariably  used  for  the  toning-bath,  as  it  is  necessary  that  the  electro-gilding 
action  should  take  place  with  a  salt  of  gold  in  solution.  It  is  also  found  ad- 
vantageous that  the  solution  should  be  neutral — i.  efj  neither  acid  nor  alkaline, 
the  reduction  taking  place  more  rapidly  than  with  an  acid  solution.  The  depo- 
sition of  gold  is  further  aided  by  the  addition  of  an  acetate  or  carbonate  of  a» 
alkali,  to  form  oxychloride  of  gold.  When  the  terchloride  of  gold  alone  is 
reduced,  chlorine  is  liberated,  which  attacks  the  silver  in  the  print,  forming 
fresh  chloride  of  silver.  That  this  action  does  occur  may  be  shown  by  the 
diminished  depth  of  color  the  prints  assume  in  the  toning-bath.  The  formation 
of  an  oxychloride  of  gold  in  the  solution,  however,  somewhat  reduces  this 
change,  a  larger  deposit  of  gold  being  thrown  down  in  a  shorter  time  than  if 
the  addition  of  the  carbonate  had  been  omitted. 

188.  The  list  of  well  known  and  much  used  toning-baths  is  a  very  long  one. 
They  resemble  each  other  more  or  less  in  character.  I  add  only  one. 

The  bath  is  made  as  follows  :   Always  keep  in  stock  the  following  solutions : 

Solution  No.-l.  Dissolve  fifteen  grains  chloride  of  gold  in  fifteen  ounces  of 
water. 

Solution  No.  2.  Dissolve  a  quarter  of  a  pound  of  acetate  of  soda  in  forty- 
eight  ounces  of  water. 

To  make  the  bath,  take  of  water,  thirty  ounces;  then  add  solution  No.  1, 
three  ounces ;  and  next  add  solution  No.  2,  three  ounces.  Let  stand  a  whole 
week  before  using  ;  if  wanted  sooner,  make  it  with  hot  water. 

This  bath  will  tone  day  after  day  if  your  operations  are  small,  until  at  least 

sheet  begin  to  tone,  this  has  arrived  at  the  point  that  ten  or  twelve  years  ago  would  have 
passed  for  good,  when  pictures  were  toned  "till  all  was  blue." — M.  L.  DAGGETT. 

Now  for  the  secret  of  pure  whites,  and  the  only  way  you  can  get  them  pure.  Procure 
your  half  ounce  of  aniline  blue,  letter  I,  and  dissolve  it  in  16  ounces  of  water.  When 
your  fixing  bath  is  made  up,  add  from  15  to  20  drops  of  the  blue  to  every  40  ounces  of 
fixing  bath.  Fix  your  prints  from  12  to  15  minutes,  and  remove  to  a  strong  solution  of 
salt  and  water.  Let  them  remain  five  minutes,  and  then  gradually  dilute  with  fresh 
water,  so  that  the  change  of  temperature  will  not  be  so  sudden,  and  you  will  never  be 
troubled  with  blisters,  and  will  always  have  pure  whites. — FRANK  THOMAS. 

188.  For  splendid  violet-black  tones  I  recommend  the  following :  Water,  2  ounces ; 
chloride  of  gold,  1  grain ;  benzoate  of  ammonia,  4  or  5  grains. 

It  is  a  variation  of  Lea's  bath,  but  much  simpler  to  prepare.  The  bath  is  very  regular. 
— Photo.  Archiv. 


454        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 


four  sheets  have  been  toned,  and  when  apparently  exhausted,  throw  away  six 
or  ten  ounces  of  it,  and  add  a  similar  quantity  of  fresh  bath,  made  according  to 
the  same  formula,  taking  care  its  age  is  not  less  than  one  week,  as  the  acetate 
bath  if  used  too  new,  would  tone  unevenly,  and  the  prints  would  lack  that 
brilliancy  so  easily  obtained  when  the  bath  is  of  the  proper  age. 

Always  take  the  prints  out  when  of  a  purplish  brown,  but  never  at  the  rusty 
.brown  stage. 

If  the  washing  has  been  carefully  done,  you  will  find  that  nearly  all  of  the 
batch  will  be  finished  about  the  same  time,  vignetted  portraits  first,  and  then 
the  plain  portraits.  The  latter  always  take  up  the  larger  proportion  of  gold. 

189.  When  the  toning  is  finished,  pour  your  bath  back  into  the  jug  or  bottle, 
and  keep  the  same  for  next  time.  Should  there  be  a  slight  deposit  of  chloride 
at  the  bottom,  decant  carefully,  so  as  not  to  disturb  it ;  this  will  save  all  filter- 
ings, which  are  always  better  avoided. 

According  to  the  minuteness  of  the  grains  of  gold,  so  will  the  print  assume, 
by  reflected  light,  colors  varying  from  purple  to  the  ordinary  yellow.  The 
organo-chloride  of  silver  appears  through  this  layer  of  gold,  and  the  colors  of 
the  two  mingling  together  give  the  different  tones  in  ordinary  prints.  When 
a  print  is  overtoned  it  becomes  blue ;  this  is  due  to  the  greater  amoun  t  of  gold 

I  use  phosphate  of  soda  in  toning.  My  method  is  to  make  two  solutions:  No.  1. 
Phosphate  of  soda,  15  grains ;  nitrate  of  potash,  10  grains ;  water,  2  ounces.  No.  2.  Chlo- 
ride of  gold  and  sodium,  4  grains;  water,  1  ounce. 

To  each  three  sheets  of  albumen  paper,  take  2  ounces  of  No.  1,  same  of  No.  2,  and  4 
to  6  ounces  of  water. 

I  use  the  gold  solution  until  entirely  spent.  When  weak,  begin  the  toning  in  that 
which  is  already  partly  exhausted,  and  finish  in  fresh. — W.  F.  WILDE. 

We  all  know  how  perplexing  it  is  when  one  is  toning  to  have  to  stop  and  get  two 
bricks  to  place  under  a  toning-bath  to  raise  it  so  we  can  use  an  alcohol  lamp.  Usually 
one  end  is  higher  than  the  other,  so  the  solution  runs  all  to  one 
end  ;  then  the  lamp  heats  all  in  one  spot. 
I  have  a  tin  stand  three  inches  high,  just 
the  size  of  the  bottom  of  the  toning- 
dish  (Fig.  355). 

The  top-piece  is  one-quarter  of  an  inch 
~7  from  the  bottom-piece,  which  forms  a 
=4  hot-air  chamber.  The  bottom-piece  has 
\J  a  large  hole  in  it,  covered  with  a  loose 

piece  of  tin  (Fig.  356). 

The  lamp-flame  strikes  the  loose  piece  and  fills  the  chamber  with  hot  air,  which  warms 
the  whole  top  evenly.  This  also  makes  a  fine  thing  to  dry  plates  on. — S.  L.  PLATT. 


FIG.  355. 


FIG.  356. 


PRINTING    ON    ALBUMEN    PAPER.  455 

deposited  over  the  surface  of  the  silver.  The  change  in  color,  on  the  immer- 
sion of  a  print  in  the  fixing-bath,  is  due  to  the  solubility  of  the  chloride  of 
silver. 

190.  Fixing  is  the  next  operation. 

Hyposulphite  of  soda  is  almost  invariably  used  for  fixing.  A  strong  fixing- 
bath  is  recommended,  on  the  ground  that  a  double  hyposulphite  of  soda  and 
silver  is  formed,  and  that  this  double  salt  is  soluble  in  hyposulphite  of  soda. 
Consequently,  if  only  enough  hyposulphite  of  soda  be  added  to  form  the  double 
salt  in  the  paper,  the  fixing  is  imperfect ;  whilst  an  excess  of  hyposulphite  will 
dissolve  it  out  of  the  paper,  and  leave  the  print  amenable  to  washing.  On 
these  grounds  the  strength  of  the  fixing-bath  has  been  made  as  follows  :  Hypo- 
sulphite of  soda,  4  ounces ;  water,  1  pint. 

Mem. :  One  ounce  of  hyposulphite  of  soda  will  fix  with  safety  three  sheets  of 
paper. 

190.  Hyposulphite  of  soda  should  be  bought  by  the  keg,  kept  as  far  away  from  other 
articles  as  possible,  to  prevent  stains.  All  washing  and  toning-trays  should  be  washed 
and  removed  before  touching  the  hypo.  Mix  the  hypo  in  a  large  crock,  using  one  pint 
of  soda  to  two  and  a  half  gallons  of  water,  which  should  be  a  little  warm — not  too  warm, 
though,  as  warm  hypo  will  bleach  prints  too  much.  By  keeping  the  bath  in  the  crock 
after  using,  it  can  be  used  twice  without  any  risk.  After  fixing  prints,  place  them  in  a 
salt  solution  for  five  minutes,  to  guard  against  blisters.  I  have  never  been  troubled  with 
blisters  with  the  above  baths,  but  it  is  better  to  be  sure,  therefore  I  have  always  continued 
to  use  the  salt  bath.  Galleries  that  have  no  stationary  zinc  or  asphaltum-lined  washing 
tanks,  should  get  a  box  larger  than  the  other  trays,  line  it  with  zinc  or  asphaltum,  and 
have  a  false  perforated  bottom  to  it.  A  hose  should  be  attached  to  this  tank  under  the 
false  bottom,  and  the  prints  should  be  washed  in  running  water  all  night,  the  water 
running  slow.  The  large  prints  are  generally  washed  separate  and  under  the  tap. — 
CHARLES  KRAUSS. 

I  will  now  proceed  to  describe  my  combined  toning  and  fixing  process : 

Solution:  Water,  32  ounces;  hyposulphite  of  soda,  8  ounces;  acetate  of  soda,  4 
drachms ;  chloride  of  gold,  15  grains. 

Dissolve  the  gold  previously  in  an  ounce  of  water,  and  then  add  it  to  the  stock  solu- 
tion. Keep  the  stock  solution  in  an  open  bath  all  the  time,  and  add  to  it  fresh  gold  and 
hyposulphite  when  required.  It  is  a  good  plan  to  dissolve  fifteen  grains  of  the  gold  salt 
in  two  ounces  of  water,  and  add  a  drachm  of  the  solution  to  the  bath  each  time  or  day 
just  before  you  are  going  to  tone.  Throw  into  the  solution  also,  about  half  an  ounce  of 
hyposulphite  of  soda  after  each  day's  severe  strain  upon  it.  In  this  way  it  will  work  for 
a  long  time,  care  being  taken  to  supply  fresh  water  as  it  becomes  exhausted  by  evapora- 
tion or  connection  with  each  print  when  removed  from  the  bath.  The  solution,  too,  is 
always  ready  and  in  good  working  condition  to  receive  the  prints  direct  from  the  pres- 
sure-frame without  any  previous  washing.  In  this  way  the  bath  is  seldom  over-crowded 


456        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

191.  Between  toning  and  fixing,  it  is  well  to  wash  the  prints  slightly.    After 
taking  them  out  of  the  toning-bath  they  should  be  placed  in  a  dish  of  water, 
face  downwards,  till  a  bath  is  ready  for  fixing. 

It  will  be  noticed  that  the  toning  action  on  the  print  continues  during  this 
washing,  presumably  by  the  solution  of  gold  contained  in  the  pores  of  the 
paper  continuing  to  deposit.     The  addition  of  a  small  quantity  of  common  salt ' 
has  been  found  useful  to  stop  this  action.     If  this  precaution  be  not  taken,  the 
prints  first  toned  should  be  left  redder  than  it  is  intended  they  should  remain. 

The  prints  should  be  immersed  in  the  fixing-bath  for  twelve  or  fifteen  min- 
utes. They  should  be  kept  in  motion  during  the  whole  time  of  fixing,  as  for 
toning.  Care  should  be  taken  to  brush  off  all  bubbles  that  may  cling  to  their 
surfaces,  as  the  cushion  of  air  impedes  the  access  of  the  liquid  to  the  silver  salt. 

192.  When  the  prints  are  fixed  they  will  appear  colorless  in  the  whites,  and 
free  from  red  patches  in  the  dark  portions. 

In  some  establishments,  it  has  been  found  advantageous  to  add  a  drachm  of 
ammonia  to  each  pint  of  fixing  solution.  The  ammonia  aids  the  rapidity  of 

with  prints  at  the  same  time,  for,  as  one  goes  in,  another,  in  general,  is  ready  to  be 
removed  to  the  water-dish. — PROF.  J.  TOWLER. 

191.  Washing  the  Prints. — This  is  always  an  important  operation,  and  must  be  thor- 
ough.   We  need  not  dwell  upon  this  part;  all  know  how  to  wash  their  prints,  and  have 
their  own  way  and  notions  of  doing  the  work — do  it  thoroughly.     Finally,  wash  or  soak 
them  in  a  solution  of  common  salt,  which  removes  the  last  traces  of  the  hyposulphite  of 
soda;  wash  them  again  in  fresh  water,  and  then  dry  them.     So  prepared,  the  silver 
picture  is  more  brilliant  and  vigorous  than  when  toned  according  to  our  more  modern 
plan ;  it  remains  to  be  seen  whether  it  is  equally  permanent.     Numerous  yellow  prints 
toned  in  this  manner  some  years  ago,  attest  to  the  contrary ;  but  we  believe  that  in  those 
days  the  same  care  in  washing  was  not  observed  as  is  now  observed ;  for  several  prints 
before  us,  that  were  toned  in  the  mixed  bath  then,  are  still  as  fresh  and  white  in  the 
whites,  as  the  best  prints  now  when  taken  from  the  wash-tub.    If  the  fact  of  permanency 
can  be  proved  to  be  a  fact,  we  have  no  hesitation  then  in  pronouncing  the  mixed  toning- 
and  fixing-bath  as  the  easiest,  the  most  economical,  and  the  most  reasonable  of  all. 
existing  toning  and  fixing  methods. — PROF.  J.  TOWLER. 

192.  Washing  Prints. — Washing-tanks  are  easily  procured  as  follows:    Get  a  set  of 
boxes;  all  sizes  required  have  one-inch  wood.     Buy  some  good  white  oil-cloth  to  line 
them  with.     Cut  it  large  enough  to  cover  the  whole  inside  and  to  lap  over  the  top  an 
inch.     Make  some  thick  starch  or  glue ;  paste  or  glue  the  whole  inside  thoroughly,  using 
plenty  of  material.     Rub  the  cloth  down  thoroughly  to  prevent  it  from  puffing  up.     The 
corners  are  then  folded  properly,  and  the  cloth  is  tacked  to  the  outer  edge  of  the  tray. 
Such  trays  can  be  used  for  toning  and  silvering  (the  silvering  tray  is  flat,  of  course),  and 
are  perfectly  safe  if  kept  clean. 


PRINTING    ON    ALBUMEN    PAPER. 


457 


fixing ;  it  also  attacks  the  size  of  the  paper,  dissolving  it  out  in  a  great  measure. 
This  renders  the  washing  more  perfect,  and  is  found  to  prevent  "  blistering," 
which  is  common  with  so  many  albumenized  papers. 

The  prints  should  be  withdrawn  slowly  from  the  bath,  in  order  that  all 
excess  of  the  hyposulphite  solution  may  be  drawn  from  them  by  capillary 
attraction,  and  placed  in  a  trough  of  water.  The  methods  of  eliminating  the 
soda,  or  of  washing  the  prints,  must  depend  upon  the  resources  of  the  pho- 
tographer. 

Washing  prints.  Place  prints  into  the  water,  face  down,  one  at  a  time.  They  are 
then  turned  face  up,  and  kept  in  constant  motion  to  prevent  the  chloride  from  settling 
to  the  face  of  the  prints.  After  a  few  minutes  change  the  prints  into  another  water, 
while  the  first  water  is  put  in  a  barrel,  the  chloride  being  settled  with  salt  or  sulphuret 
of  potassium,  When  sulphuret  is  used,  the  hypo  (developer),  etc.,  can  be  saved  in  the 
same  barrel,  which  is  done  in  a  great  many  galleries. 

Into  the  third  water,  pour  an  ounce  of  commercial  acetic  acid  to  acidify  the  prints. 
Allow  them  to  turn  cherry  red,  keeping  them  well  in  motion  to  prevent  them  from 
acidifying  uneven,  which  would  result  in  uneven  tones.  Wash  them  twice  more,  then 
place  them  in  a  tank  of  warm  water.  This  is  done  to  avoid  chilling  the  toning-bath 
every  time  you  change  prints.  If  this  water  is  warm  enough,  it  will  keep  the  toning-bath 
in  the  same  temperature  (lukewarm).  Get 
another  tank,  with  water,  to  which  add  a  small 
handful  of  salt;  in  this  tank  the  prints  are 
placed  after  toning.  The  salt  prevents  the 
prints  from  toning  any  further,  and  also  guards 
against  blisters  in  the  hypo. — CHAS.  KRAUSS. 

The  cut  shown  (Fig.  357)  represents  my 
automatic  siphon  washing-tank.  It  will  be 
seen  that  I  dispense  with  any  rocking  motion 
to  fill  the  siphon. 

I  use  what  is  known  in  the  trade  as  "strong" 
lead  pipe,  f  inch.  The  reason  for  using  it  is 
that  it  will  bend  without  kinking.  My  tank 
is  21  x  28  x  8J,  and  it  fills  and  empties  every 
fifteen  minutes.  It  gets  the  water  through  a 
hose,  direct  from  the  tap. 

Now  the  size   can  be  made  to  suit  water- 
supply  and  any  amount  of  business  done.     I 
use  a  wooden  tray  with  a  perforated  bottom,  allowing  an  inch  space  all  around  the  sides 
and  bottom  of  tank,  so  the  prints  will  drain  off. 

The  other  large  pipe  is  to  clean  the  tank  out,  and  the  small  one  on  the  siphon  is  to 
drain  it  out  in  the  winter  to  keep  it  from  freezing. 

The  tank  is  well  coated  with  asphaltum  varnish,  and  will  last  a  long  time  if  kept  so. 
I  wash  prints  three  hours,  and  find  it  enough. — GEORGE  W.  LEAS. 


FIG.  357. 


CHAPTEE   XIX. 

PRINTING DRAWBACKS   AND    DEFECTS;   CAUSES   AND    REMEDIES. 

193.  THERE  is  no  department  of  the  art  of  photography  that  rewards  the 
careful  worker  so  satisfactorily  as  printing.  But  as  printers  are  not  always 
careful,  drawbacks  and  defects  are  met.  To  turn  them  aside  we  must  not  only 
be  able  to  recognize  them  when  we  meet  them,  but  we  must  know  their  causes 
and  have  remedies  at  hand  which  will  strike  at  the  very  root. 

Trials  and  tribulations  are  liable  to  present  themselves  at  all  stages  of  the 
operation.  Sometimes,  however,  their  eifects  are  not  discovered  until  the  work 
is  almost  done  and  the  prints  are  ready  for  the  finishing. 

I  draw  a  line  between  drawbacks  and  defects.  The  drawbacks  come  and 
go  with  change  of  season,  and  vary  according  to  the  care  of  the  printer.  When 
the  silver  solution  and  the  toning-bath  are  not  replenished,  poor  prints  will 
follow.  That  is  a  drawback.  So  is  neglect  to  wash  the  hands  between  the 
operations  apt  to  cause  very  serious  drawbacks.  A  dry-plate  negative,  if  not 
most  thoroughly  washed  free  from  hypo,  will  spoil  all  the  prints  made  with  it, 
especially  if  the  air  or  paper  is  moist,  and  cause  a  serious  and  wasteful  draw- 
back. Any  carelessness  creates  a  drawback. 

Some  defects  I  have  already  hinted  at.  I  tried  to  mention  all  I  ever  heard 
of  in  Photographies,  and  history  is  not  to  be  repeated  here.  Coarse  and  spotty 
paper,  impure  chemicals,  weak  negatives,  blisters,  and  hypo  cause  the  majority 
of  them.  The  remedies  I  leave  to  the  notes. 

193.  Again,  another  topic — clean  hands.  It  is  much  more  easy  to  keep  them  from 
being  stained  than  to  remove  stains  when  made.  The  remedy  is  care  and  dexterity  of 
manipulation.  I  would  recommend  the .  use  of  a  pair  of  good  dog's  skin  gloves,  well 
rubbed  with  warm  wax  or  paraffine,  as  being  comfortable  to  wear,  and  effectually  keeping 
the  fingers  clean.  India-rubber  gloves  answer  the  purpose  very  well,  but  some  are  very 
unpleasant  to  wear.  I  mention  this  subject  not  so  much  to  call  attention  to  appearances 
as  to  affecting  the  health  of  the  operators.  I  quite  believe  eruptions  upon  the  hands  we 
hear  so  much  about  might  be  entirely  avoided  if  the  operator  was  rather  more  imbued 
with  the  spirit  of  economy  and  manipulatory  neatness.  For  my  part,  I  always  look  on 
so  many  stains  as  so  much  wasted  material. — EDWARD  DUNMORE. 
(458) 


DRAWBACKS    AND    DEFECTS  ;    CAUSES    AND    REMEDIES.        459 

194.  During  the  past  few  years  there  has  been  quite  a  revolution  in  the  use 
of  paper.  Formerly  Rives  paper,  owing  to  its  tender  quality,  was  used  for 
small  prints  only.  Its  manufacture  having  been  improved,  it  is  now  almost 
universally  used,  and  its  once  fierce  and  tougher  rival  is  laid  aside.  But' with 
this  change  came  another,  namely,  an  increase  of  blisters.  I  have  no  cause  to 
describe  them.  I  know  no  remedy  except  extreme  care  as  to  the  uniform 
temperature  of  the  various  solutions.  There  are  those,  however,  who  "know 
a  sure  preventive,"  and  they  shall  generously  speak. 

194.  For  over  a  year  I  have  not  been  troubled  with  a  blister.  I  am  using  the  N.  P.  A. 
Dresden  paper  exclusively.  All  that  is  necessary  to  head  off  blisters  is  to  use  alum  in 
the  fixing-bath.  I  give  the  formula  I  have  been  using  for  over  a  year : 

Printing  bath,  fifty  grains,  slightly  acid,  with  C.  P.  nitric  acid  ;  when  foul,  add  one- 
half  drachm  liquor  ammonia,  sun  a  few  days,  filtering. 

After  printing,  I  wash  in  rapid  changes  of  water  until  the  water  remains  perfectly 
clear ;  then  in  acetic  acid,  one  drachm  to  one  quart  of  water,  until  the  prints  are  evenly 
reddened ;  then  in  three  changes  of  water ;  tone,  wash  in  two  changes  of  water,  then  fix 
in — Hyposulphite  of  soda,  round  handful ;  water,  2  quarts ;  alum  (dissolved  in  warm 
water),  2  drachms;  Aniline  blue  (1  m.  to  oz.  solution),  1  drachm.  (The  aniline  blue  I 
make  after  Wilson's  Photographies,  page  222,  note  284.) 

Fix  from  ten  to  fifteen  minutes ;  wash  through  three  changes  of  water,  then  from  five 
to  ten  minutes  through  acetate  of  lead  water,  then  through  three  changes  of  water.  (The 
acetate  of  lead  I  keep  in  stock — Acetate  of  lead,  1  ounce ;  hot  water,  7£  ounces.  For 
use,  £  ounce  to  1  quart  of  water.)  Drain  all  prints  on  a  sheet  of  glass ;  place  between 
blotting  paper,  with  light  pressure,  for  about  fifteen  minutes ;  take  out,  place  in  pile 
under  light  pressure,  and  mount  at  leisure. 

As  to  the  alum,  I  read  so  much  about  it  that  I  concluded  to  try  it  in  the  fixing-bath 
in  place  of  bicarbonate  of  soda,  and  find  it  works  admirably ;  never  a  blister. — HENRY 
LISTER. 

Blisters  are  due  simply  to  the  employment  of  too  strong  and  too  freshly  prepared 
toning  and  fixing  solutions.  I  found  this  out  by  remarking  that,  for  some  days  running, 
blisters  were  to  be  observed  upon  the  carte-de-visite  pictures,  while  others,  prepared  from 
exactly  the  same  description  of  paper,  were  altogether  free  from  the  defect  On  nearer 
inquiry,  I  discovered  that  my  assistant  was  in  the  habit  of  commencing  work  by  toning 
and  fixing  the  small  pictures,  while  the  larger  ones  were  left  till  the  last,  and  treated, 
consequently,  in  weaker  solutions.  To  convince  myself  of  the  truth  of  this  circumstance, 
I  directed  that  on  the  following  day  a  weaker  solution  should  be  used,  and  found  then 
that  my  paper  remained  free  from  blisters. — FRANZ  FRIEDRICH. 

My  remedy  for  measles  is  this :  Silver  the  paper  the  evening  before  it  is  to  be  used ; 
dry  and  fume  it,  and  lay  it  on  an  open  shelf  in  a  dry  room.  This  plan  enables  the 
printer  to  get  his  frames  filled  early  the  next  morning,  and  thus  utilize  all  the  light. 
The  paper  keeps  perfectly. 

I  have  no  theory  to  offer  for  the  above  statement,  but  it  works  well  in  practice,  and 


460         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

195.  Perhaps  the  greatest  difficulty  the  printer  must  meet  is  in  securing 
the  thorough  removal  of  traces  of  hyposulphite  of  soda  from  the  prints. 
Samples  of  paper  and  hyposulphite,  and  water,  too,  vary,  and  thought  must  be 
exercised  in  this  matter  with  great  constancy. 

Thorough  washing  is  a  safe  remedy,  but  it  does  not  succeed  always,  unless 
the  prints  are  treated  individually.  Sorry  looking  prints,  disgracing  the  pho- 
tographer, follow  any  lack  of  conscientious  care  in  this  department. 

that  is  the  essential  point.  Should  you  have  an  attack  on  some  of  the  cold  mornings, 
don't  throw  your  paper  away  in  disgust,  but  lay  it  aside  on  a  dry  shelf  until  next  day, 
and  the  chances  are  that  it  will  print  smoothly. 

Let  me  also  remind  you  ef  an  old  dodge  to  prevent  paper  from  curling  up  when  first 
placed  on  the  silver  solution.  Get  a  flat  curtain  stick,  and  cut  it  in  two ;  put  a  tack  in 
each  stick  to  lift  it  up  by,  and  as  soon  as  the  sheet  is  placed  on  the  solution,  quickly  lay 
a  stick  at  each  side,  on  top  of  the  sheet,  so  near  the  edge  that  it  cannot  curl.  Try  it,  and 
save  your  breath,  for  you  will  need  do  no  more  blowing  in  that  direction. 

Thirdly,  should  you  be  troubled  with  those  very  large  blisters  or  bubbles  that  some- 
times put  in  an  appearance  in  the  fixing-bath,  put  some  salt  right  into  the  fixing-bath 
when  you  mix  it.  It  will  prevent  blisters,  and  if  harmful  to  the  finished  prints,  let  some 
photo-chemist  speak. — FRANK  BOBBINS. 

195.  Great  care  should  be  taken  to  remove  all  the  silver  from  the  prints  before  toning; 
this  washing  should  be  done  in  rain  or  distilled  water,  and  on  no  account  should  salt  be 
added  until  they  are  well  washed. — JOHN  STUART. 

My  mode  of  working  and  the  results  of  using  J.  R.  Clemons's  "alum  process"  for 
eliminating  hyposulphite  of  soda  from  photographic  prints,  is  thus :  I  take  my  prints 
from  the  hypo  and'  immediately  immerse  them  in  a  saturated  solution  of  alum,  letting 
them  remain  from  ten  to  twenty  minutes ;  I  keep  them  moving  continually ;  then  remove 
them  and  rinse  them  thoroughly  in  clean  soft  water.  This  process  I  repeat  four  times, 
taking  particular  care  to  rinse  them  well  each  time ;  then  mount  them.  If  my  prints  are 
thoroughly  washed  before  toning,  so  as  to  remove  all  free  nitrate,  they  come  out  of  the 
alum  bath  clear  and  bright,  and  so  far  stand  the  test  better  than  when  I  did  not  use  the 
alum.  I  consider  John  R.  Clemons's  "  alum  process  "  one  of  the  greatest  improvements 
in  the  art. — HOWARD  M.  SEDGWICK. 

I  have  succeeded  in  finding  a  test  for  hypo  which  is  at  least  very  simple.  It  is  based 
on  the  reaction  of  hypo  on  iodide  of  starch.  When  you  add  hypo  to  iodide  of  starch,  the 
same  is  discolored  instantly ;  the  more  concentrated  the  iodide  of  starch,  the  more  hypo 
will  be  necessary  for  discoloration  ;  if,  therefore,  a  very  dilute  solution  of  hypo — such,  for 
instance,  as  the  water  in  which  prints  have  been  washed — is  to  be  tested,  a  very  dilute 
iodide  of  starch  will  be  necessary. 

I  prepare  the  same  in  the  following  manner :  One  part  of  arrowroot  is  dissolved  in  a 
little  cold  wate^  and  afterward  about  100  parts  of  boiling  water  are  added.  In  this 
manner  I  obtain  a  colorless  solution  of  starch;  this  solution  of  starch  is  mixed  with  one- 
fifth  of  a  straw-colored  solution  of  iodine  in  iodide  of  potassium;  this  gives  a  beautiful 


DRAWBACKS    AND    DEFECTS;   CAUSES    AND    REMEDIES.        461 

196.  Sometimes  impure  cardboard  will  cause   the  turning  and  fading  of 
prints  after  they  are  mounted.     Hyposulphite  of  soda  is  employed  in  the 
manufacture  of  paper  and  unless  it   is  thoroughly  eliminated,  it  will  cause 
mischief.      "With  the  productions  of  our  well  known  cardboard  makers  in 
America  there  can  hardly  be  any  fear  in  this  direction. 

197.  Sometimes  silver  becomes  a  very  destructive  element  in  paper  prints, 
• 

blue  solution  of  iodide  of  starch,  which  will  keep  for  several  weeks,  and  might  be  kept 
on  hand  by  stockdealers.  If  the  water  in  which  prints  have  been  washed  is  added  to 
this  solution  of  iodide  of  starch,  it  of  course  becomes  diluted,  and  consequently  paler, 
even  if  the  water  is  perfectly  pure ;  this  might  easily  be  mistaken  for  a  discoloration, 
therefore  it  will  be  better  to  proceed  in  the  following  manner :  take  two  test-tubes  of 
about  equal  diameter,  and  put  in  each  of  them  about  a  cubic  centimetre  of  iodide  of 
starch ;  add  to  the  one  about  eight  times  as  much  pure  water,  of  the  same  kind  as  has 
been  used  for  washing,  and  to  the  other,  the  same  quantity  of  water  in  which  the  prints 
have  been  washed,  and  it  will  then  only  be  necessary  to  shake  both  test-tubes  up  well, 
and  hold  them  against  a  piece  of  white  paper  and  compare  them ;  even  by  lamp-light  it 
is  an  easy  matter  to  discover  discoloration,  if  the  same  has  taken  place.  The  easiest 
mode  is  to  look  vertically  down  into  the  tubes.  I  have  tried  this  process  carefully,  and 
find  that  when  only  one-millionth  part  of  hypo  is  present,  a  distinct  discoloration  takes 
place.  On  account  of  this  extraordinary  sensitiveness,  great  cleanliness  in  the  glasses 
and  the  hands  is  required. — DR.  H.  W.  VOGEL. 

196.  Mounting-boards  are  the  cause  of  much  of  the  fading  of  photographs,  and  I  sug- 
gest the  following  method  as  a  preventative : 

Our  prints  must  be  mounted;  and,  as  paper  boards  are  the  only  thing  on  which  we 
can  mount  them,  we  must  do  our  best  to  check,  if  possible,  the  bad  effects  of  hyposul- 
phite and  other  deleterious  matter  in  the  boards  injurious  to  photographs.  The  mode  I 
propose  is  to  saturate  the  prints  with  collodion. — JOHN  STUART. 

After  careful  experiment  I  have  concluded  that  freshly-made  starch,  paste,  and  glue, 
either  in  watery  or  alcoholic  solution,  may  be  thoroughly  relied  on  as  safe  mountants, 
and  that  when  fading  occurs  in  prints  mounted  with  either  of  these  substances,  it  may 
fairly  be  concluded  that  it  has  not  been  caused  by  the  mounting  material. 

I  am  aware,  of  course,  that  such  a  negative  conclusion  does  not  help  to  indicate  the 
true  cause  of  fading ;  but  it  is  quite  evident  that  the  greater  the  number  of  probable 
causes  that  we  can  eliminate,  the  more  nearly  will  we  approach  to  a  solution  of  the 
difficulty  which  has  so  long  been  a  puzzle  to  the  experimentalist  in  silver  printing. — 
DR.  E.  LIESEGANG. 

197.  The  existence  of  silver  in  the  highest  lights,  the  purest  whites  of  the  finished 
picture,  cannot  be  looked  upon  otherwise  than  as  a  very  great  evil.     So  long  as  it  is, 
there  are  far  fewer  chances  for  the  permanence  of  the  print,  and  if  any  way  could  be 
found  for  removing  it,  without  injury  to  the  rest  of  the  picture,  it  would  be  a  great 
advantage.    This  is  a  very  difficult  problem,  and  one  which  I  have  as  yet  been  unable 
to  solve. — M.  CAREY  LEA,  M.D. 


462         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

attacking  them  with  all  the  ferocity  of  a  blood  disease.  A  learned  contempo- 
rary has  given  much  careful  attention  to  this  subject  and  provides  some  very 
valuable  instruction,  but  does  not  offer  a  cure. 

198.  Over-printing  should  not  occur  as  a  rule,  and  when  it  does,  generally 
the  best  and  easiest  remedy  is  to  cast  aside  the  defective  print  and  make  an- 
other.    Oftentimes,  however,  say  at  the  close  of  the  day,  when  the  silvered 
paper  is  exhausted,  that  would  be  impossible.     In  case  an  order  must  be  filled 
on  time,  a  method  of  reducing  an  over-printed  picture  would  prove  &  boon. 

199.  The  improper  drying  of  prints,  after  washing,  also  causes  much  loss. 
Whatever  the  means  of  drying,  the  whole  print  should  have  a  uniform  chance 
to  dry.     If  globules  of  water  are  permitted  to  hang  upon  the  prints ;  or  if 
they  are  permitted  to  adhere  to  each  other  in  part,  or  it  they  are  dried  upon 
cards  or  between  papers  that  are  unclean  they  will  show  defects  which  render 
them  unfit  for  use. 

If  photographers  would  think,  there  would  be  no  occasion  for  alluding  to 
these  matters  at  all.  Given  a  defect  or  drawback,  the  cause  would  be  then 
known  and  the  remedy  applied  at  once. 

199.  The  best  plan  we  have  seen  adopted  for  drying  prints  by  the  sheets  is  as  follows : 
The  prints,  taken  out  of  the  water  one  by  one,  are  laid  upon  well-washed  pieces  of  linen 
till  each  "sheet"  is  covered ;  another  sheet  is  then  placed  on  the  top  to  be  covered  with 
prints,  followed  by  another  sheet,  and  so  on  till  all  are  arranged.  A  little  gentle  pres- 
sure then  removes  the  greater  part  of  the  moisture,  and  the  prints  are  now  placed  between 
sheets  of  blotting  paper  for  a  final  drying,  where  they  are  left  till  ready  for  sorting  or 
cutting. 

Some  photographers  use  linen  cloths  only,  others  merely  blotting-paper  or  board. 
Now,  this  double-drying  plan,  carried  out  in  its  integrity,  is  very  good,  but  most  particu- 
lar care  has  to  be  taken  that  the  routine  is  thoroughly  followed  day  after  day.  No 
holiday  time  and  short  hands,  no  press  of  work,  no  oversight,  no  neglect  in  consequence 
of  a  bad  printing  day  leaving  few  prints  to  attend  to,  can  be  permitted  to  interfere  and 
allow  a  batch  of  prints  to  be  left  in  the  sheets  over  the  day,  or  everything  will  go  wrong. 

Perhaps  the  most  popular  method  is  to  hang  up  the  prints  by  American  clips  till  quite 
dry,  and  it  is  one  which  has  much  in  its  favor,  the  only  foreign  enemy  being  dust,  and 
that  can  easily  be  guarded  against  if  there  be  suitable  space  at  command.  One  chief 
drawback  to  the  use  of  the  clip,  beyond  the  space  required  for  hanging,  is  the  liability 
of  the  prints  (if  on  paper)  having  a  gloss  at  all  beyond  the  average,  to  show  when  quite 
dry  a  multitude  of  fine  cracks,  which  gives  the  mounted  print  a  very  unsightly  appear- 
ance. There  is  no  remedy  for  this  except  taking  the  prints  down  before  they  are  quite 
dry,  or  drying  between  sheets  of  cloth  or  blotting-paper. — British  Journal. 


CHAPTER   XX. 


PRINTING-ROOM   PARTICULARS. 

200.  THE  cutting  and  preparation  of  the  paper  for  the  printing-room 
require  a  great  deal  of  nice  care.  The  first  should  be  done  economically,  and 
the  second  with  as  little  fingering  of  the  silvered  surface  as  possible.  A  hundred 
little  wrinkles  and  dodges  will  occur  to  the  tasteful  printer  who  puts  heart  in 
his  work.  These  are  the  result  of  "  knack "  and  can  scarcely  be  taught  by 
another  I  have  however  culled  a  few  notes  of  experience  which  tally  with 
my  own  and  have  shaped  them  so  they  may  be  readily  followed. 

200.  The  bath  I  use  is  from  30  to  40  grains  strong,  containing  a  strong  dose  of  nitrate  of 
ammonium,  and  is  alkaline  from  the  same.  The  sheets  are  immersed,  face  up,  one  at  a 
time  until  from  ten  to  twenty  are  covered  by  the  solution.  The  dish  being  rocked  back 
and  forth  to  loosen  bubbles  and  make  sure  that  each  sheet  is  thoroughly  wet,  I  then 
turn  the  whole  mass  over,  which  brings  the  first  ones  immersed  to  the  top,  face  down. 
The  next  operation  is  as  follows :  Have  a  sheet  of  double  thick  glass,  a  little  larger  than 
the  paper  (I  am  speaking  of  whole  sheets  of  paper),  which  place  at  a  proper  inclination 
to  drain  the  surplus  solution  back  into  the  bath.  Float  the  paper  to  one  side  of  the  bath 
to  get  them  even,  then  take  them  all  out  together  and  lay  them  face  down  on  the  inclined 
sheet  of  glass,  near  enough  to  the  top  to  be  held.with  two  wooden  clips,  one  at  each  end ; 
the  drainage  is  now  all  back  into  the  bath  (Fig. 

358).    To  hasten  this  operation  I  use  a  squeegee,  •FlG>  358- 

a  strip  of  rubber  set  into  a  stick  a  foot  or  more 
long,  which  is  applied  lengthwise  at  the  top  of 

the  paper  and  pressed  forward 

toward  the  bottom,  forcing  the 

solution  out  of  the  paper  into 

the  bath  (Fig.  359).     If  desired 

to  secure  the  largest  amount  of 

silver  absorbed  by  the  paper 

press  the  solution  from  the  top 

sheet,  then  the  next,  and  so  on,  or  the  whole  can  be  squeegeed  at  once.  What  I  claim 
for  paper  so  prepared  is  greater  depth  and  transparency  to  the  picture,  and  perfect  uni- 
formity in  the  paper,  with  facility  and  equable  toning.  The  paper  prints  clear  through, 
giving  great  body  to  the  darker  parts.  On  the  score  of  economy  of  silver  I  think  the 
loss  less  than  when  paper  is  hung  up  to  drain  (on  the  floor]  in  the  usual  way.  The 

(463) 


FIG.  359. 


464 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


201.  The  fuming  of  the  paper  is  considered  a  great  point  among  American 
printers,  although  in  some  countries  it  is  not  practised  at  all. 

The  paper  should  be  well  dried  after  silvering  before  this  operation  is 
attempted,  or  else  nothing  but  yellow  prints  will  be  returned  for  your  labor. 
And  some  careful  thought  must  be  devoted  to  the  operation,  as  the  time  of 
fuming  is  governed  by  the  character  of  the  sample  of  paper  used.  One  is 
never  justified  in  plunging  headlong  over  any  road,  even  though  it  be  a 
familiar  one.  The  careful  person  always  comes  out  best.  Any  contrivance  by 

saving  of  time  in  silvering  by  this  method  would  largely  overbalance  the  waste  of  silver 
by  extra  absorption,  if  there  be  any. — JOHN  L.  GIHON. 

201.  The  construction  of  my  fuming  box,  I  think,  can  easily  be  seen  from  the  accom- 
panying diagrams.  In  Fig.  360,  I  have  purposely  left  the  front  out  of  the  box.  A  A  BB 
are  the  grooves  that  the  frames  slide  into.  It  can  be  made  to  take  any  number  of  frames. 
Mine  will  fume  six  sheets  at  a  time,  and  is  about  all  I  require  at  one  fuming.  We  have 
never,  since  using  the  box,  had  one  case  of  uneven  fuming,  but  the  paper  works  splen- 
didly at  all  parts  of  the  sheet.  As  soon  as  the  paper  is  ready,  we  take  about  one  ounce 
o'f  ammonia  (which  will  fume  enough  for  all  day  and  more)  in  a  saucer,  and  put  in  cham- 
ber, having  previously  ascertained  that  the  box  was  "closed;"  put  in  frames  with  paper, 
shut  down  top  cover,  one  pull  at  the  ring  handles  shown  in  the  front  of  the  box,  "  and  off 
she  goes"  When  fumed  enough,  push  back  handles  again,  open  cover,  take  out  paper, 

and  as  the  paper  goes  out,  so  will  the  small 
quantity  of  "  exhausted  "  ammonia.  In  the  mean- 
time, that  in  the  chamber  is  gathering  fresh 
strength  from  the  saucer,  and  is  fully  charged 
for  the  next  batch.  In  Figs.  361  and  362,  I 
have  shown  the  end  and  side  sections.  It  will 
be  seen  that  the  bottom,  which  the  inside  box 
slides  upon,  and  also  the  sides,  are  carried  from 
front  to  back,  and  supported  in  this  way.  The 


FIG.  360. 


FIG.  361. 


FIG.  362. 


inside  box  is  about  two  inches  shorter,  which  will  be  just  enough  to  open  or  close  the 
holes  when  slid  either  way.  It  is  best  not  to  have  it  any  shorter  than  is  absolutely 
necessary,  as  then  there  will  be  no  danger  of  pushing  it  too  far  either  way.— S.  H. 
PARSONS. 


PRINTING-ROOM    PARTICULARS. 


465 


means  of  which  the  sensitized  paper  may  be  sufficiently  reached  by  the  fumes 
of  ammonia  will  answer,  yet  it  will  be  found  well  to  have  a  carefully  planned 
fuming  box  even  for  small  operations.  A  good  model  is  given  below,  with  full 
instructions  for  use. 

202.  Proper  pressure-frames  are  a  great  essential.  And  they  must  be  pres- 
sure-frames, such  as  will  secure  the  close  and  uniform  contact  of  the  paper  with 
the  negative  or  film  to  be  printed.  As  the  press  printer  by  "making  ready" 
— by  "  underlaying "  and  "overlaying"  secures  all  possible  effect  from  the 

202.  As  to  the  breaking  of  negatives,  that  is  to  be  avoided  in  various  ways — by  using 
elastic  packing,  and  not,  as  some  do,  sheets  of  paper,  or  mill-board.  By  not  leaving  the 
negatives  in  the  closed  frame  and  under  pressure  after  the  printing  is  done.  But  most 
of  all,  by  using  thicker,  stronger,  and  flatter  glass  than  is  generally  done. 

Some  may  be  disposed  to  say,  What  is,  after  all,  the  need  of  so  much  pressure?  Why 
is  it  not  sufficient  to  apply  the  paper  with  a  gentle  pressure  to  the  negative,  without 
forcing  it  into  contact  so  strongly  ? 

I  answer,  if  we  would  carefully  calender  our  paper  after  sensitizing  and  drying  (after 
fuming,  if  that  is  to  form  part  of  the  preparation),  we  would  require  much  less  pressure, 
for  then  we  should  have  two  surfaces  flat,  or  so  nearly  flat,  that  a  moderate  pressure 
would  bring  them  into  contact.  But  our  silvered  paper  is  not  thoroughly  smooth  and 
even.  And  the  albumen,  coagulated  by  the  bath,  is  more  or  less  horny,  so  that  the  paper 
is  not  very  flexible,  and  does  not  easily  fit  itself  closely  even  to  a  plain  surface.  To  bring 
it  into  close  contact,  pressure  is  required,  and  no  inconsiderable  amount. — M.  CAREY 
LEA,  M.D. 

I  send  you  a  drawing  of  a  printing-frame  I  have  for  making  aquatints,  similar  to  the 
mezzotints  (Fig.  363).  A  is  the  outside  of  the  frame,  made  of  walnut,  6  inches  square 
and  1}  inches  thick,  but  rabeted  out  f  inch  on  the 
sides,  to  let  the  cover  down  flush  with  the  top, 
as  you  will  see,  and  then  fastened  with  a  little  catch 
at  C.  B  B  is  the  cover  hinged  on  to  the  frame,  6 
inches  long,  but  £  inch  narrower,  to  let  it  down 
into  the  frame,  f  inch  thick,  and  just  a  piece  of 
board  with  two  strips  on  the  edges  to  prevent 
warping.  D  is  a  cross  bar,  that  slides  in  grooves 
in  the  frame  A,  and  is  to  hold  the  negative  with 
the  help  of  the  thumbscrew  E,  FF  are  two  little 
pieces  \\  inches  wide  and  3  inches  long,  hinged  to 
the  cover  to  hold  the  paper,  and  are  made  thickest 
at  the  outer  edge. 

The  operation  of  the  frame  is  very  simple.  Fas- 
ten your  paper  on  to  the  cover  with  the  little  clamps,  which  will  keep  it  straight,  and 
fasten  your  negative  with  the  thumb-screw,  putting  it  back  from  the  paper  as  far  as  you 
choose,  and  thus  you  get  your  picture  without  "printing  through  any  transparent  sub- 

30 


FIG.  363. 


466         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

engraving,  so  should  the  photograph  printer  secure  his  best  results  by  means  of 
the  close  contact  suggested.  I  have  often  seen  a  large  print — say  a  full  sheet — 
ruined  by  a  fuzzy  spot  here  and  there  caused  by  a  little  crinkle  in  the  paper 
or  a  tiny  curve  in  the  glass  preventing  close  contact.  A  bit  of  cotton,  a  small 
rag,  or  even  a  single  thickness  of  paper  in  addition  to  the  regular  padding, 
would  prevent  all  such  blemishes.  Watch  everything. 

For  special  styles  of  prints  like  medallions,  prints  with  a  halo,  mezzotints, 
fabric  pictures,  and  vignettes  a  dozen  contrivances  will  suggest  themselves  to 
every  ingenious  printer  to  whom  mother  necessity  need  only  make  a  suggestion 
to  secure  a  proper  invention  to  answer  the  purpose.  For  small  work  the  ordi- 
nary "flat"  printing-frame  answers  admirably,  but  for  larger  sizes  the  "deep" 
construction  is  noi:  only  stronger  but  safer  for  glass  plates.  As  an  additional 
protection  to  the  negative  a  plate  glass  should  be  supplied  with  every  printing- 
frame. 

203.  The  favorite  style  for  portraiture  is  the  vignette.  It  is  considered  "  the 
most  artistic"  by  many.  Its  strong  rival  is  the  "  medallion."  There  was  a 
time  when  vignettes  properly  graded  were  very  difficult  to  secure,  and  a  higher 

stance"  and  also  secure  much  better  effects.  The  idea  is  to  create  a  small  space  between 
the  negative  and  the  paper. — FORESTER  CLARK. 

Those  who  are  accustomed  to  printing  photographs  on  handkerchiefs  and  other 
fabrics,  know  what  a  trouble  it  is  to  get  the  same  drawn  tight  and  even,  and  to  hold 

them  so  during  printing.  A  little  device  we  use 
answers  the  purpose  admirably,  and  is  very  simple. 
Take  any  ordinary  porcelain  printing-frame,  and 
through  the  bottom  part  bore  a  hole,  say  2£  inches 
in  diameter.  Fit  this  with  a  nice,  smooth,  tapering 
cork,  so  that  the  further  it  is  pushed  up  through  the 
hole  the  tighter  the  fit.  Now  over  the  face  and 
small  end  of  the  cork  lay  the  fabric,  push  it  up 
through  the  hole  in  the  printing-frame,  and  thus 
you  secure  a  surface  as  hard,  even,  and  easily  printed 
upon,  as  a  piece  of  ground  porcelain.  The  cut  (Fig. 
364)  will  make  the  whole  matter  plain.  The  hole 
does  not  prevent  the  frame  from  being  used  for 
porcelains,  either. — MOORE  BROTHERS. 

203.  The  drawing  (Fig.  365)  will  show  how  I  use 
the  Waymouth  Vignette  Papers.  I  do  not  consider 
the  process  of  nailing  the  strips  of  board  on  the  out- 
side of  the  printing-board  (to  which  the  papers  are  nailed  or  tacked,  as  shown  in  the 
drawing),  as  the  very  best  way  for  quickness  in  arranging  the  papers,  but  I  have  the  strips 


PRINTING-ROOM    PARTICULARS.  467 

price  was  asked  for  them.  But  now  the  Waymouth  vignette  paper  and  other 
contrivances  render  the  process  an  easy  and  regular  one.  There  is  always  room 
for  the  exercise  of  taste  in  deciding  how  much  of  the  person  should  be  indicated 
in  a  vignette — how  much  "bust" — how  much  "sky."  A  little  practice  will 
soon  teach  the  eye  to  judge  quickly.  A  nice  style  that  seems  to  have  fallen 
into  disuse  is  made  by  vignetting  full  and  three-quarter  standing  and  sitting 
figures.  They  are  a  pleasant  relief  from  the  rather  common  bust  picture.  Use 
your  genius. 

204.  Combination  printing  is  attempted  more  than  formerly.  The  objection 
to  it  is  the  time  it  requires,  and,  moreover,  as  a  rule,  the  results  are  not  con- 
sidered artistic.  An  artist  who  succeeds  admirably  in  making  them  artistic, 
however,  is  my  esteemed  colleague,  Mr.  H.  P.  Robinson.  His  excellent 
manual  of  instructions  must  be  consulted  by  all  who  are  ambitious  to  follow 
him.  These  will  be  so  few,  that  I  am  not  warranted  in  appropriating  more 

constantly  near  by,  and  as  it  does  not  take  many  seconds  to  tack  one  or  two  thicknesses 
on  the  outside  of  the  printing- frame,  for  the  purpose  of  separating  the  paper  more  or  less 
from  the  negative  to  get 
soft  vignettes,  I  therefore 
use  this  way.  When,  after 
having  built  up  the  out- 
side of  the  frame  by  means 
of  strips  of  backboard,  and 
when,  upon  looking  at 
the  print,  if  there  should 
be  too  much  blending  out  at  the  dark  drapery  of  the  print,  although  the  grading  may 
be  beautiful  around  the  head,  it  can  easily  be  overcome  by  removing  one  or  more 
of  the  strips  of  wood  nailed  on  the  bottom  of  the  frame,  and  where  the  lower  part  of  the 
vignette  paper  is  placed,  and  thus  bringing  that  part  of  the  vignetting  paper  nearer  to 
the  negative  (leaving  the  rest  of  the  paper  as  before),  and  then  as  the  distance  between 
the  two  is  diminished,  there  will,  of  course,  not  be  so  much  blending. 

Another  thing:  in  placing  these  papers  on,  place  the  negative  in  the  frame  first,  hold 
it  up  to  the  light  with  one  hand,  and  match  the  paper  to  the  negative  by  placing  it  on 
the  further  side  of  the  frame,  and  looking  through  to  the  light,  being  careful  not  to  let 
too  much  space  above  the  typ  of  the  head,  as  it  will  then  print  too  dark. — CHARLES  W. 
HEARN. 

204.  For  combination  printing  the  landscape  negative  must  have  a  dense  sky,  or,  if  it 
be  weak  or  have  any  defects,  it  must  be  stopped  out  with  black  varnish.  In  this  case  it 
is  better  to  apply  the  varnish  to  the  back  of  the  glass ;  by  this  means  a  softer  edge  is 
produced  in  printing  than  if  painted  on  the  varnished  surface.  With  some  sujbjects, 
such  as  those  that  have  a  tolerably  level  horizon,  it  is  sufficient  to  cover  part  of  the  sky 
while  printing,  leaving  that  part  near  the  horizon  gradated  from  the  horizon  into  white. 


468         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

than  a  few  notes  from  his  work.  I  heartily  commend  the  production  of  com- 
bination pictures  as  most  excellent  schooling,  sure  to  bring  good  returns. 

205.  I  have  already  alluded  to  some  of  the  various  styles  printed  from  the 
photographic  negative,  but  there  are  many  others.  Many  of  our  leading  artists 
resort  to  styles  all  their  own.  I  cull  from  these  a  few  suggestions,  which  will 
be  useful  to  the  tasteful  and  inventive  printer  in  producing  many  more. 
Quality  should  ever  be  the  first  thing  in  style. 

One  kind  of  style  (?)  should  be  studiously  avoided,  namely,  that  of  orna- 
menting portraits  with  the  shocking  borders  and  make-up  margins  one  often 
sees.  The  introduction  of  anything  incongruous  should  always  be  resisted. 
Scratching  and  etching  upon  the  negative  are  bad.  Flying  angels  and  plumed 
birds  have  no  place  in  the  human  portrait.  When  you  hunger  after  such 
incongruities  seek  out  some  of  the  advertisements  of  our  railroad  "  trunk  lines," 
and  ye  shall  be  filled.  Anything  introduced  in  a  picture  which  detracts  from 
the  special  object  of  interest,  is  incongruous  and  out  of  taste. 

It  may  here  be  remarked  that  in  applying  black  varnish  to  the  back  .of  a  negative, 
occasions  will  often  be  found  where  a  softened  or  vignetted  edge  is  required  for  joining, 
where  a  vignette  glass  or  cotton-wool  cannot  be  applied.  In  such  cases  the  edge  of  the 
varnish  may  be  softened  off  by  dabbing  slightly  before  it  is  set,  with  the  finger,  or,  if  a 
broader  and  more  delicately  gradated  edge  be  required,  a  dabber  made  with  wash-leather 
may  be  employed  with  great  effect. 

When  an  impression  is  taken,  the  place  where  the  sky  ought  to  be  will,  of  course,  be 
plain  white  paper ;  a  negative  of  clouds  is  then  placed  in  the  printing-frame,  and  the 
landscape  is  laid  down  on  it,  so  arranged  that  the  sky  will  print  on  to  the  white  paper 
in  its  proper  place.    The  frame  is  then  exposed  to  the  light,  and  the  landscape  part  of 
the  picture  is  covered  up  with  a  mask  edged  with  cotton-wool.     The  sky  is  vignetted 
into  the  landscape,  and  it  will  be  found  that  the  slight  lapping  over  of  the  vignetted 
edge  of  the  sky  negative  will  not  be  noticed  in  the  finished 
print.    There  is  another  way  of  vignetting  the  sky  into  the 
landscape,  which   is,  perhaps,  better  and  more  convenient. 
Instead  of  the  mask  edged  with  cotton-wool,  which  requires 
moving  occasionally,  a  curved  piece  of  zinc  or  cardboard  is 
used.     Here  is  a  section  of  the  arrangement  (Fig.  366).     The 

straight  line  represents  the  sky  negative,  and  the  part  where  it  joins  the  landscape  is 
partly  covered  with  the  curved  shade.  Skies  so  treated  must  not,  of  course,  be  printed 
in  sunlight.— H.  P.  ROBINSON. 

205.  The  method  I  use  is  simple,  and  requires  no  labor.  I  have  applied  it  in  different 
ways  for  marginal  printing,  for  monograms  and  autographs  on  portraits,  and  descriptive 
lettering  on  views  in  landscape  photography. 

For  portraits  it  is  as  follows :  I  first  make  a  print  for  the  usual  medallion  style,  mask- 
ing out  the  mat  part.  After  the  print  is  made  I  insert,  between  the  print  and  the  glass 


PRINTING-ROOM    PARTICULARS  469 

206.  "  Keeping  tally  " — i.  e.,  keeping  an  account  of  how  many  prints  have 
been  made  toward  the  filling  of  an  order — is  a  tax  to  the  memory,  and  there- 
fore the  plan  given  below  will  prove  useful.     One  or  two  prints  should  always 
be  made  in  excess,  to  provide  for  failure  in  the  after  operations. 

207.  The  printer  in  a  large  establishment  has  often  been  compared  to  a 
manufacturer  making  many  styles  of  goods  each  day,  and  no  two  days  alike. 
This  is  literally  true  and  just,  for  there  is  always  a  lack  of  uniformity,  both  in 
quality  and  in  subject,  in  the  negatives  which  come  to  his  hands.      He  is 

which  holds  the  oval  mask,  a  thin  sheet  of  paper,  such  as  is  used  for  foreign  correspond- 
ence, upon  which  the  autograph  is  written  or  the  monogram  drawn  or  printed  in  non- 
actinic  ink,  then  exposed  to  the  light  for  a  short  time.  When  for  landscape  it  is  difficult 
to  get  paper  sufficiently  large,  I  do  the  lettering  reversed  on  a  glass  that  holds  the  mask 
'which  prints  the  outside  tint  or  mat.  The  best  thing  I  have  found  for  lettering  is 
Gihon's  Opaque. 

The  mats  for  portraits  can  be  embellished  very  much  by  designs  drawn  on  the  same 
kind  of  paper.  French  note  paper  with  fancy  designs,  used  in  the  same  manner,  makes 
very  good  mats. — J.  LANDY. 

The  following  will  be  found  a  durable  process  for  securing  the  tinted  picture  called 
"Au  deux  crayons :" 

Make  two  solutions,  viz. :  No.  1.  Aloes,  powdered,  1  ounce;  alcohol,  12 ounces.  No. 
2.  Water,  12  ounces;  liq.  ammonia,  15  drops. 

Immerse  the  albumen  prints  in  solution  No.  1,  until  they  take  a  bright  lemon  color  ; 
then  wash  them  well,  and  put  them  in  solution  No.  2.  Let  them  remain  until  they  take 
a  warm  orange  color,  and  again  wash  them.  Mount  and  touch  up  the  whites  with 
Chinese  or  any  good  white,  and  the  blacks  with  India-ink.  After  touching  up  the  whites 
and  blacks,  coat  the  pictures  with  the  following:  Plain  collodion,  6  ounces;  castor  oil, 
12  drops. 

The  deeper  the  tint  required,  the  longer  the  prints  must  remain  in  the  aloes  solution. 
Too  long  immersion  in  the  ammonia  solution  will  reduce  the  tint. — WILLIAM  BELL. 

207.  To  secure  a  good  print  from  a  hard  negative  I  make  a  positive  on  glass  from  the 
negative,  and  when  a  print  in  the  pressure-frame  has  acquired  sufficient  depth  in  the 
shadows,  I  use  the  transparent  positive  as  a  mask,  placing  it  outside  the  pressure-frame 
over  the  image.  As  this  mask  is  opaque  in  the  shadows  and  transparent  in  the  lights,  it 
will  be  seen  that  the  printing  in  the  shadows  is  stopped  or  retarded,  whilst  in  the  lights 
it  still  progresses ;  the  detail  and  modelling  in  the  face  are  thus  gradually  secured  with- 
out the  minor  lights,  which  give  transparency  to  the  shadows,  being  obliterated  or  over- 
done. It  will  be  seen  that  some  judgment  must  be  exercised  in  using  such  a  mask,  as, 
if  it  were  applied  too  soon,  the  negative  and  its  inverse  counterpart  neutralzing  each 
other,  would  issue  in  negation  of  all  detail.  The  want  of  sharpness,  which,  at  first  sight, 
it  would  seem,  should  follow  from  placing  such  a  mask  outside  of  the  printing-frame,  is 
not  found  in  actual  practice. — SAMUEL  FRY. 

To  obtain  brilliant  tints  from  flat  negatives  "extra  brilliant  "  paper  is  recommended. 


470         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

governed  very  much  in  his  work,  therefore,  by  the  negatives  supplied  him. 
They  are  "  weak,"  "  strong/'  "  harsh  and  hard/'  "  soft/'  and  what  not,  and 
should  be  studied  carefully  before  they  are  placed  in  contact  with  a  single  piece 
of  paper.  Then  the  paper  must  be  prepared  and  the  light  chosen  to  suit  the 
varied  characters  of  the  plates  in  hand.  But  it  is  such  a  fascination  to  see 
excellent  and  uniform  results  created  by  his  care  and  thought,  that  the  earnest 
printer  is  only  too  ready  to  practise  all  the  deftness  of  his  art  upon  his  subjects. 

but  the  effect  of  the  quality  obtained  by  glossy  papers  is  rather  that  of  brilliancy,  such  as 
is  produced  by  varnishing,  than  an  actual  increase  in  the  contrast  between  the  higher 
lights  and  the  shadows ;  but  for  negatives  only  slightly  deficient  in  density  nothing  more 
will  be  required. 

When,  however,  the  negative  requires  still  greater  effects  of  contrast  other  means  must 
be  resorted  to.  One  of  the  most  successful  modes  of  effecting  this,  to  a  certain  degree,  is* 
of  so  simple  a  nature  as  almost  to  raise  a  presumption  against  the  possibility  of  its  use- 
fulness. It  consists  in  applying  to  the  back  of  the  negative  a  yellow  coating,  which  is 
most  easily  done  by  dissolving  iodine  in  the  ordinary  negative  varnish,  and  coating  as 
though  varnishing  the  film. 

.  We  have  communicated  this  to  friends,  and  have  found  them  apply  it  to  the  film  under 
the  idea  that  the  iodine  played  some  part  in  strengthening  the  deposit  of  silver.  Such 
is  not  its  action.  A  negative  yellow  varnished  at  the  back  will  give  prints  possessing  a 
striking  amount  of  brilliancy  from  negatives  that  would  otherwise  print  faint  and  flat. 
The  advantage  of  this  method  is  that  it  can  be  used  in  conjunction  with  other  plans,  and 
thus  intensify  the  effect  of  the  other.  For  example:  When  a  negative  is  too  weak  to 
give  a  good  print  with  either  extra-brilliant  paper  or  yellow  varnishing,  if  both  are  com- 
bined it  may  be  quite  possible  to  get  excellent  results.  In  the  case  of  a  negative  still  too 
weak  to  print  well  when  even  both  these  methods  are  combined,  further  plans  entail  an 
extra  amount  of  labor,  but  still  not  to  a  prohibitive  degree.  Such  a  negative  will  require 
fumed  paper. — British  Journal. 

Extremely  soft  and  beautiful  prints  having  the  appearance  of  being  printed  from  finely 
retouched  negatives  are  done  by  the  " Berlin "  process.  I  use  Hance's  "Ground-glass 
Substitute,"  which  gives  to  glass  coated  with  it  a  most  beautiful  ground-glass  surface. 
Moreover,  this  substitute  gives  us  advantages  over  the  old  process,  besides  cheapness  and 
the  ease  with  which  it  may  be  obtained.  When  albumenizing  a  plate  in  the  old  process, 
the  albumen  which  run  over  on  to  the  ground  surface,  could  only  be  removed  by  clean- 
ing it  with  powdered  emery,  thus  endangering  the  film.  Now  the  "Substitute"  need  not 
be  applied  until  the  negative  is  entirely  finished,  even  to  varnishing. 

The  whole  process  as  at  present  worked,  therefore,  stands  thus:  Albumenize  the  glass 
and  make  the  negative  soft,  thin,  and  full  of  detail  in  the  usual  way ;  varnish  and  coat 
the  reverse  side  with  Hance's  ground -glass  substitute,  and  print  in  soft  light.  This  is 
not  a  mezzotint  process.  The  effect  is  apparent  over  the  whole  picture,  and  is  not  lost 
in  the  shadows ;  we  think  it  only  needs  to  be  tried  to  be  liked.  Best  of  all,  it  may  be 
applied  to  negatives  already  made  with  the  best  of  success,  so  that  it  is  easily  tried,  and 
no  charge  for  the  secret. — G.  W.  WALLACE. 


PRINTING-ROOM    PARTICULARS.  471 

208.  "  Glace  "  or  "  enamel "  pictures  are  comiDg  into  use  again.  For  a  time 
the  "shine"  of  the  burnisher  drove  them  out.  They  have  their  attractions  as 
well  as  the  matt  surface  of  platinum  and  bromo-gelatiue  papers ;  and  some 
insist  that  the  "  happy  medium  "  surface  of  the  albumen  print,  simply  rolled 
or  treated  with  cerate,  is  the  most  approved.  All  shall  have  attention  here. 

208.  For  a  fine  finish  with  the  "glace"  or  "enamel"  use  plate  glass,  or  the  first 
quality  of  French  negative  glass  will  answer. 

Clean  the  best  side  in  an  ordinary  manner,  and  when  perfectly  dry  apply  very  lightly, 
with  cotton-wool,  a  little  prepared  chalk ;  then,  with  a  soft  brush,  dust  the  plate,  and 
gum  the  edges  with  any  kind  of  gum.  Before  the  gum  is  dry,  collodionize  the  plate 
with  plain  collodion — consistency  of  collodion  as  will  flow  well.  The  next  thing  is  to 
soak  for  one  or  two  hours  one  ounce  white  French  gelatine  in  eight  ounces  settled  water, 
and  dissolve  fully  by  heat.  While  yet  hot,  strain  through  a  piece  of  muslin  into  a  small 
porcelain  dish ;  immerse  your  print  in  this  solution,  and  when  well  saturated  take  it  out, 
scraping  the  back  of  the  picture  over  the  edge  of  the  dish,  to  avoid  waste.  Place  the 
print  down  on  your  prepared  plate  and  press  out  the  air-bubbles  by  means  of  a  piece  of 
sheet  rubber  five  inches  long  and  two  and  one-half  inches  wide,  inserted  into  a  wooden 
handle,  like  the  well-known  rubber  squeegee. 

Now,  when  the  picture  thus  put  on  glass  is  nearly  dry,  damp  a  two-ply  piece  of  bristol- 
board,  previously  cut  to  size ;  paste  on  one  side,  put  it  over  the  print,  pressing  it  well 
down  with  the  scraper,  especially  the  edges. 

The  Mounting. — After  thirty-six  hours,  or  when  perfectly  dry,  cut  the  picture  with  the 
point  of  a  knife  along  the  edge,  leaving  about  one-quarter  of  an  inch  strip,  and  raise  the 
picture  slowly ;  then  trim  to  size  and  gum  the  edges  only ;  place  down  on  the  card,  and 
for  a  weight,  cover  it  with  the  same  glass  from  which  you  cut  it,  or  any  piece  of  glass 
that  is  straight  and  clean.  All  dust  and  carelessness  must  be  avoided  or  a  bad  result  is 
certain. 

You  can  put  one  or  more  prints  on  one  glass,  only  be  careful  to  keep  away  from  the 
edge  about  half  an  inch  or  so.  Keep  the  gelatine  solution  as  cool  as  you  can  work  it. 

If  the  picture  leaves  the  glass  quite  clean,  you  can  use  it  again  without  recleaning ; 
thus  you  may  use  it  a  lifetime,  being  cleaned  but  once. — JOHN  A.  SCHOLTEN. 

I  wish  to  present  a  wrinkle  given  me  by  a  friend.  You  will  notice  that  this  print  has 
a  very  fine  gloss,  and  this  is  produced  simply  by  taking  the  print  out  of  the  washing 
trays  and  squeegeeing  it  on  a  marble-top  table.  When  the  print  is  dry,  it  remains  flat. 
This  one  is  a  little  crooked  there,  on  account  of  being  in  proximity  with  my  heated 
body.  It  was  printed  on  ready  sensitized  paper,  eight  months  old,  and  the  printing, 
toning,  washing,  and  drying  occupied  but  a  few  minutes  less  than  one  hour.  After 
fixing,  it  was  treated  with  the  alum  bath. — JOHN  H.  J  ANEW  AY,  M.D. 

While  on  this  subject,  I  would  like  to  say  that  I  read  a  few  days  ago  that  it  is  possible 
to  get  a  gloss  on  gelatine  prints  with  the  ordinary  ferrotype  plate.  I  have  prints  here 
about  a  year  old,  and  simply  moistened  them  and  placed  them  on  a  tintype,  and  you  see 


472         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

209.  After  all  the  care  possible  in  printing,  unless  pictures  are  mounted 
upon  tasteful  cards,  and  in  a  cleanly  manner,  they  will  be  utterly  spoiled. 
Clean  and  sweet  mountants  must  also  be  used,  and  cardboard  free  from  dele- 

the  result.     [He  pulled  the  prints  off  from  the  varnished  side  of  the  plates  and  passed 
them  around.]     The  reason  I  have  brought  this  matter  up  is  that  some  time  ago  we  had 

quite  a  discussion  in  regard  to  the  use  of  hand- 
finished  vulcanized  rubber,  which  was  so  hard  to 
obtain,  so  I  saw  the  suggestion  of  using  the  ferrotype 
plate,  and  I  find  that  it  works  very  well,  and  that  the 
pictures  strip  off  as  easily  as  when  on  rubber. — F.  C. 
BEACH,  M.D.,  at  N.  Y.  Photo.  Society. 

For  the  enamelled  cameo  or  glace  portrait  process, 
I  use  a  press  as  represented  in  Fig.  367.  Any  car- 
penter will  make  one  for  about  three  dollars.  It  is 
made  of  maple  wood,  three-quarter  inch  thick.  The 
raised  centre  for  moulding  is  glued  on.  The  top  and 
bottom  are  hinged  together. — E.  D.  ORMSBY. 

209.  Now  comes  the  question  as  to  whether  the 
pictures  should  be  mounted  wet  or  dry,  and  what 
particular  adhesive  material  should  be  used.  A  happy 
medium  between  the  two  conditions  of  the  paper 
should  be  chosen.  The  photographs  should  be  suffi- 
ciently damp  to  prevent  their  curling  up,  and  insure 
their  lying  flat;  they  should  not  be  dripping  wet. 
This  state  can  readily  be  obtained  by  allowing  them 
to  lie  for  a  few  moments  between  wet  cloths.  All 
sorts  of  compositions  have  been  suggested  and  used,  but  of  them  all,  the  plain  starch- 
paste  has  remained  most  in  favor. 

From  the  commencement  of  the  application  of  our  art  to  wholesale  requirements,  such 
as  the  illustration  of  books  with  photographs,  it  has  been  a  vexatious  matter  to  mount 
the  albumenized  prints  upon  paper  sufficiently  thin  for  bookbinders'  purposes,  without 
showing  a  most  objectionable  and  unsightly  cockling  or  drawing  of  the  edges  and  corners 
of  the  supporting  paper.  The  result  can  be  perfectly  accomplished,  but,  unfortunately, 
the  method  entailed  involves  too  much  labor  for  the  occasion.  The  following  is  from 
one  of  my  "scraps,"  and  answers  tolerably  well. 

The  only  mounting  material  hitherto  in  use,  by  which  all  risk  of  cockling  is  avoided, 
is  India-rubber  in  solution,  but,  unfortunately,  it  is  altogether  untrustworthy ;  sooner  or 
later,  the  prints  are  sure  to  leave  the  mounts. 

The  cause  of  cockling  in  prints  mounted  on  thin  boards  is,  of  course,  well  known.  A 
print  treated  with  starch-paste,  gum,  or  any  adhesive  preparation  of  which  water  forms 
a  large  part,  absorbs  the  water  and  swells  or  stretches.  If,  in  this  condition,  it  is  attached 
to  a  dry  board,  it  contracts  again  as  the  water  evaporates,  and  necessarily  drags  the 
board  to  which  it  is  attached  out  of  shape,  causing  cockling  or  buckling.  The  point  to 


PRINTING-ROOM    PARTICULARS. 


473 


FIG.  368. 


FIG.  369. 


terious  substances  employed,  if  the  pictures  are  intended  to  last  at  least  one 
generation. 

be  secured,  then,  is  an  adhesive  substance  containing  little  or  no  water.  India-rubber 
solution  answers  this  condition,  but,  as  I  have  shown,  it  fails  in  other  respects. — JOHN 
L.  GIHON. 

To  make  the  best  paste  brush:  1st.  Procure  a  cork-puller,  an  implement  used  for 
removing,  or  rather  extracting,  corks  from  the  inside  of  bottles.  2d.  Purchase  a  fine 
sponge,  free  from  any  grit  or  sand,  and  insert  the  same  in 
your  cork-puller,  leaving  about  one  inch  extending  to  serve 
as  the  brush;  now  push  down  the  sliding  ring,  and  the 
sponge  will  be  held  firm  and  steady.  (Figs.  368  and  369.) 
Make  your  paste  of  the  proper  consistency,  and  use  but  little 
on  the  brush.  The  entire  cost  of  this  contrivance  will  not 
exceed  twenty-five  or  thirty  cents,  and  will  last  you  three 
times  as  long,  work  nicer,  smoother,  and  quicker  than  any 
ordinary  hair  brush.  The  same  size  sponge  will  do  equally 
well  for  any  size  photo.,  from  card  to  14  x  17.  Having 
finished  your  mounting,  remove  the  sponge  from  the  holder, 
wash  well,  squeeze,  and  lay  aside  for  future  use. 

A  brush  of  the  same  construction  may  be  used  with  ad- 
vantage in  the  dark-room,  for  removing  the  surplus  water 
from  dry  plates  after  the  final  washing.  It  will  absorb  the 
Avater  and  particles  of  sand  quicker  than  a  camePs-hair  brush. 
Keep  the  wires  dry,  to  prevent  corroding. — EMIL  FREY. 

In  the  first  place,  a  picture  that  has  not  been  mounted  upon  a  proper  mount  is  not 
susceptible  of  the  best  finish ;  but  supposing  it  is  properly  mounted,  my  instructions  are, 
first,  to  see  that  the  picture  is  not  too  much  dried,  as  all  know  the  swell  of  the  card 
when  a  picture  is  first  mounted  bends  the  picture  backward.  Let  the  picture  dry  until 
the  contraction  of  the  paper  just  commences  to  bend  the  picture  forward.  It  will  be 
found  that  the  picture  in  this  stage  is  about  three-fourths  dry,  and  it  is  absolutely  neces- 
sary that  it  should  not  be  allowed  to  dry  any  more  than  this  until  after  the  picture  has 
gone  through  the  burnisher.  This  is  best  done  by  piling  the  pictures  in  one  or  two 
piles,  and  placing  them  under  a  weight.  They  should  be  carefully  taken  from  this  pile 
and  spotted  out,  and  immediately  placed  in  another  pile  under  weight.  The  same  pre- 
caution should  take  place  in  applying  the  lubricator  to  the  print.  They  should  be  taken 
to  the  burnisher  in  this  condition. — J.  H.  SCOTFORD. 

I  venture  to  give  my  method  of  mounting  with  Slee's  mounts.  Place  the  prints  right 
side  up  in  a  basin  of  water  at  your  left;  cut  several  sheets  of  ordinary  white  blotting- 
paper  into  halves ;  lay  one  of  these  pieces  on  the  bench,  length  from  right  to  left,  and 
spread  ten  cards  in  two  rows  on  the  paper ;  lay  the  prints  in  place  on  each  of  these, 
place  another  piece  of  the  blotting-paper  over  them,  and  roll  the  whole  first  lightly  with 
a  common  kitchen  rolling-pin,  and  afterward  heavier.  The  blotters  serve  again  after 
drying,  till  soiled.  These  mounts  are  great  labor  savers. — JOHN  L.  GIHON. 


CHAPTEE   XXI. 

PECULIAR   PRINTING   PROCESSES. 

210.  BESIDES  the  method  of  printing  on  albumen  paper — the  one  most  com- 
monly used,  and  the  one  treated  in  Chapters  XVIIL,  XIX.,  and  XX. — 
there  are  several  other  processes  for  producing  positives.  Some  of  them  are  on 
paper  and  some  on  glass.  Some  attention  will  be  given  to  each  one  in 
what  follows : 

READY  SENSITIZED  PAPER,  or  paper  washed  and  fumed  after  sensitizing, 
is  now  in  common  use,  especially  among  amateurs.  Its  convenience  is  undis- 

210.  The  process  I  have  now  adopted  is  as  follows:  Sheets  of  blotting-paper  are 
steeped  in  a  solution  of  bicarbonate  of  soda  and  dried.  The  strength  of  the  solution  is 
not  of  importance ;  I  use  an  almost  saturated  one,  but  I  believe  a  weaker  one  would 
answer.  The  silver  bath  should  be  made  neutral  by  the  addition  of  bicarbonate  of  soda 
until  there  is  a  permanent  precipitate,  and  allowing  this  precipitate  always  to  remain  in 
the  bottle  in  which  the  solution  is  kept.  Float  the  paper  for  the  usual  time,  perhaps  a 
little  longer,  and  then  absorb  the  superfluous  silver  solution  by  placing  the  paper  between 
folds  of  blotting-paper.  When  almost,  but  not  quite  dry  the  sensitive  paper  is  inter- 
leaved with  the  already  prepared  blotting-paper,  and  the  whole  put  under  a  slight  pres- 
sure. Paper  prepared  in  this  way  will  retain  its  whiteness  for,  at  the  very  least,  a  month, 
and  probably  longer;  thus  a  large  stock  can  be  made  at  anytime,  to  last  for  weeks,  which 
is  always  at  hand  ready  for  use.  If  an  insufficient  number  of  prints  be  produced  in  a 
day  to  be  worth  toning,  they  can  be  kept  until  the  following  day  by  replacing  them 
between  the  sheets  of  blotting-paper.  This  process  is  particularly  useful  for  amateurs, 
who  can  print  one  day  and  leave  the  toning  and  fixing  until  they  have  another  oppor- 
tunity.— EDWARD  SMITHELLS. 

There  is  a  great  deal  being  said  in  the  transatlantic  journals  about  washed  paper^ 
that  will  keep  in  its  sensitized  condition  for  longer  or  less  time.  I  give  you  a  formula 
that  I  find  will  keep  the  paper  I  use,  for  three  or  four  days  in  perfect  condition,  without 
washing  or  the  trouble  of  fuming  pads  or  paper. 

Silver  Bath. — Nitrate  of  silver,  480  grains,  water,  16  ounces.  Dissolve,  and  add  a  few 
drops  of  concentrated  aqua  ammonia,  and  then  add  nitrate  of  ammonia,  1  ounce. 

For  giving  pure  whites  and  many  other  excellent  qualities,  I  recommend  the  E.  A. 
paper.  ^ 

This  paper  is  floated  on  the  silver  solution  for  one  minute ;  it  is  then  drawn  over  the 
sharp  edge  of  the  dish,  for  the  purpose  of  removing  all  the  surface  solution,  and  laid  face 
(474) 


PECULIAR    PRINTING    PROCESSES.  475 

puted,  because  it  is  always  ready.  For  the  large  printer  it  would  be  expensive 
and  troublesome.  Its  preparation  is  held  as  a  secret  by  several  who  manu- 
facture it.  It  was  first  made  by  washing  the  paper  right  after  silvering,  then 
drying  and  storing,  and  when  needed  for  use  the  sensitiveness  which  the  re- 
moval of  the  free  nitrate  of  silver  had  destroyed  was  restored  by  fuming  with 
ammonia.  The  keeping  qualities  were  secured  by  the  use  of  citric  acid  in  the 
silver  bath,  say  ten  grains  of  citric  acid  to  each  ounce  of  a  forty-grain  nitrate 
solution. 

It  is  not  recommended  to  small  consumers  to  manufacture  it,  yet  for  general 
information  some  useful  hints  are  given  for  what  they  may  be  worth. 

211.  Plain  paper,  or  matt  surface  paper,  was  in  vogue  until  albumenized 
paper  drove  it  nearly  out  of  use.  It  still  does  good  service,  however,  where  a 
matt  or  plain  surface  is  needed  for  coloring,  India-ink  work,  and  so  on.  It 
is  sometimes  called  "  arrow-root "  paper.  It  now  has  several  compeers  in  the 

downward  on  a  quire  of  common  paper,  such  as  is  used  for  printing  newspapers,  then 
lay  a  couple  of  sheets  of  the  same  paper  on  the  top  of  the  sensitized  sheet,  and  press  back- 
ward and  forward  with  your  hand,  until  all  the  solution  is  taken  up  by  the  paper  on 
which  it  is  laid,  remove  the  upper  sheets  and  hang  the  paper  up  to  dry ;  serving  the 
next  sheet  of  sensitized  paper  the  same  way,  and  on  the  same  paper  as  the  first  was  laid, 
which  need  not  be  renewed  for  at  least  a  dozen  or  more  sheets  of  silvered  paper.  The 
drawing  the  paper  over  the  edge  of  the  dish,  leaves  the  paper  comparatively  free  from 
solution.  Paper  of  the  kind  mentioned  above,  will  keep  three  days  in  the  hottest 
weather.  The  silver  solution  is  weak,  and  there  is  no  waste  of  dripping.  The  next 
time  you  silver  you  remove  a  sheet  or  two  of  them,  and  put  among  the  cuttings.  After 
returning  the  silver  solution  to  the  bottle,  I  take  one  of  those  sheets  of  blotting-paper  to 
wipe  out  the  dish.  The  paper  thus  prepared  will  give  any  tone  up  to  a  pure  black,  and 
with  all  the  required  brilliancy. — JEX  BABDWELL. 

I  recommend  a  toning-bath  upon  which  M.  Carrier  lays  especial  stress,  as  necessary  to 
the  production  of  fine  pictures,  especially  if  black  tones  are  required.  It  stands  as  fol- 
lows: Chloride  of  gold  (or  double  chloride  of  gold  and  potassium),  2  grains;  chloride  of 
cadmium,  1  grain ;  sulphocyanide  of  ammonium,  K>  grains ;  water,  5  ounces. 

This  bath  gave  more  brilliant  prints,  and  it  was  not  difficult  to  obtain  a  deep  black 
tone.  I  found  the  paper  best  suited  for  very  vigorous  negatives,  yielding  soft,  delicate 
tints  from  such ;  but,  from  soft  negatives,  the  prints  had  less  vigor  than  those  obtained 
by  the  ordinary  albumenized  paper  process. 

An  ordinary  excited  albumenized  paper,  if  washed  by  floating,  face  downward,  on 
water,  will  keep  a  long  time  without  discoloration ;  but  it  is  almost  impossible  to  obtain 
vigorous  prints  from  paper  so  treated,  and,  although  these  prints  lack  some  vigor,  as  you 
will  perceive  from  examples  inclosed,  which  were  produced  from  good  but  soft  negatives, 
still,  they  are  much  more  brilliant  than  I  have  obtained  from  thoroughly  washed  sensi- 
tive albumenized  paper.— G.  WHARTON  SIMPSON,  A.M. 


476        WILSON'S  QUAKTER  CENTUKY  IN  PHOTOGRAPHY. 

platinum,  bromo-gelatine,  and  kindred  processes,  all  of  which  will  have  atten- 
tion presently.  They  will  probably  supersede  the  good  old  stand-by  altogether, 
but  it  is  entitled  to  mention  here  as  an  item  of  history. 

If,  for  an  emergency  and  in  haste,  a  sheet  of  plain  paper  is  required  for  any 
special  purpose,  it  may  be  obtained  by  a  very  simple  expedient.  Albumenized 
paper  is  floated  on  the  silver  bath  with  the  plain  side  in  contact  with  the  solu- 
tion, treating  the  albumenized  surface  as  the  wrong  side.  It  seems  that  the 
albumen  and  salt  penetrate  and  pass  through  the  paper  in  sufficient  degree,  to 
form,  when  floated  on  the  silver  solution,  a  sensitive  surface  capable  of  yielding 
an  excellent  image,  in  no  degree  inferior  to  an  ordinary  plain  paper  print — 
delicate,  vigorous,  and  of  good  tone. 

212.  As  many  attempts  have  been  made  at  the  life,  so  to  speak,  of  albu- 
menized paper  as  have  been  aimed  at  the  subversion  of  the  "  wet "  negative 
method.  But  not  with  equal  success.  Excellent  substitutes  have  been  pro- 

212.  Aristotypic  paper  is  the  name  of  a  new  paper  for  making  photographic  prints  in 
the  pressure  frame.  The  paper  is  sensitized  and  preserves  its  good  qualities  for  several 
months ;  it  should  be  kept  in  a  very  dry  place,  and  the  surface  should  not  be  touched 
with  the  fingers.  The  paper  having  been  cut  the  required  size,  is  placed  in  the  pressure 
frame  quite  dry,  as  is  done  in  the  case  of  albumenized  paper.  Print  until  the  blackest 
portions  are  a  little  metallized.  The  paper  is  much  more  sensitive  than  albumenized 
paper.  To  wash  the  prints  they  are  placed  in  water,  one  by  one,  the  printed  side  under- 
neath. The  water  is  changed  five  or  six  times,  until  it  is  no  longer  milky.  The  first 
water  should  act  in  from  three  to  five  minutes ;  it  is  kept  to  extract  the  silver,  which  is 
precipitated  by  chlorhydric  acid,  or  ordinary  salt.  From  a  sheet  of  aristotypic  paper  of 
50  to  60  centimetres  (18  sheets,  card  size),  23  grains  of  chloride  of  silver  are  obtained. 

Toning  and  fixing  in  one  bath  has  been  found  to  have  many  advantages.  The  print 
coming  out  of  the  printing-frame,  is  left  in  the  bath  till  the  color  is  arrived  at,  then 
washed  and  dried.  The  bath  is  composed  of  two  solutions,  and  will  keep  for  a  long  time. 

Dissolve :  Water,  24  ounces ;  hyposulphite  of  soda,  6  ounces ;  sulphocyanide  of  am- 
monium, 1  ounce;  acetate  of  soda,  Ij-  ounces;  saturated  solution  of  alum,  2  ounces. 

Fill  the  bottle  containing  this  solution  with  scraps  of  sensitized  paper,  bad  prints  that 
are  not  fixed,  and  leave  it  for  a  day.  Then  filter  and  add  the  following  solution  :  Water, 
6  ounces;  chloride  of  gold,  15  grains;  chloride  of  ammonium,  30  grains. 

It  is  necessary  to  print  deep  enough  and  to  leave  the  prints  in  the  bath  till,  in  looking 
through  them,  the  desired  color — brown,  dark,  or  bluish — is  observed. 

Wash  well  for  several  hours,  then  lay  the  print,  face  downward,  upon  a  ferrotype  plate 
that  has  been  cleaned  with  a  wet  sponge;  go  over  it  with  an  India-rubber  squeegee  and 
let  dry.  It  will  come  off  with  a  fine  glaze.— ED.  LIESEGANG. 

Uranium  printing.  Good  photographic  paper,  not  too  thin,  is  first  to  be  sized  with 
arrowroot  starch,  prepared  as  follows :  Some  arrowroot  is  to  be  mixed  with  three  or  four 
times  its  weight  of  cold  water,  and  left  to  stand  several  hours,  till  it  becomes  thick  dough. 


PECULIAR    PRINTING    PROCESSES.  477 

vided,  it  is  true,  but  none  which  secures  the  charm  of  a  brilliant  surface  like 
that  of  albumen  paper,  or  by  the  use  of  which  such  a  variety  of  pleasing  tones 
are  obtainable  with  the  same  ease  and  certainty  in  working. 

But  the  war  will  go  on  against  albumenized  paper  notwithstanding  the 
peculiar  beauty  of  its  results.  They  are  false  at  heart,  fugitive,  and  apt  to  fade 
away  at  the  very  time  when  one's  affections  are  most  set  upon  them. 

It  would  be  useless  for  me  to  detail  all  the  well-known  attempts  at  the 
assassination  named. 

I  have  selected  carefully  some  notes  on  those  methods  which  have  come 
nearest  to  success,  for  the  consideration  of  my  readers.  I  have  reserved  two  or 

It  is  then  to  be  poured  over  with  a  hundred  or  a  hundred  and  fifty  times  its  weight  of 
boiling-hot  water.  This  starch  is  applied  to  the  paper,  stretched  on  a  board  with  pins, 
by  means  of  a  very  soft  sponge  (sponge  digested  in  dilute  chlorohydric  acid  and  well 
washed),  first  removing  from  the  starch  the  hard  skin  which  comes  over  it  in  cooling. 

The  best  mode  is  to  fasten  all  the  sheets  down  with  pins ;  to  rub  the  upper  one  with 
one  sponge,  evenly  and  gently;  then,  to  render  still  more  even,  with  a  second;  and, 
finally,  to  complete  the  work,  with  a  flat  (2-inch)  broad  camel's-hair  pencil.  The  sheet 
is  then  detached,  hung  up  to  dry,  and  the  rest  treated  likewise. 

The  uranium  collodion  is  prepared  as  follows:  Ether,  80  grammes;  alcohol,  120 
grammes ;  pyroxyline,  2  grammes ;  castor  oil,  2  grammes ;  nitrate  uranium  20  grammes ; 
nitrate  silver,  2  grammes. 

The  nitrates  must  be  perfectly  neutral ;  a  fact  important,  as  the  commercial  nitrate  of 
uranium  is  generally  very  acid,  and  must  be  purified  by  recrystallization  several  times, 
finally  from  ether.  The  nitrate  of  silver  must  be  dissolved  in  distilled  water,  and  so 
added  to  the  collodion.  If  the  uranium  salt  is  acid,  the  collodion  is  thereby  partly 
gelatinized,  and  no  longer  flows  evenly. 

The  castor  oil  serves  to  render  the  layer  flexible,  to  make  it  adhere  to  the  paper,  and 
to  keep  the  picture  in  the  collodion  film.  It  may  be  replaced  with  other  substances;  for 
example,  with  Venice  turpentine.  The  collodion  must  be  kept  in  the  dark. 

Provide  a  board,  and  attach  the  paper  to  it,  overlapping  a  little  to  right  and  under 
sides,  and  leave  the  near  right  hand  free.  Pour  on  the  collodion  as  on  a  glass  plate. 
Pour  it  off  again  into  a  separate  bottle,  provided  with  a  funnel.  These  portions,  after 
being  properly  diluted,  to  compensate  for  the  thickening  by  evaporation,  and  filtered, 
can  be  used  over  again.  If  the  paper  by  this  treatment  becomes  transparent,  it  is  a  proof 
that  it  was  not  sufficiently  sized  with  the  starch,  and  the  picture  will  sink  in.  If  spotty, 
it  may  arise  from  the  same  cause,  or  from  an  -excess  of  oil  added  to  the  collodion. 

The  prepared  sheets  must  not  be  dried  near  a  fire  or  stove,  as  they  are  very  sensitive 
to  heat.  When  dry,  to  be  pressed  and  rolled. 

The  printing  is  not  to  be  made  any  stronger  than  is  desired  in  the  finished  print ;  on 
the  contrary,  should  be  rather  less  strong,  as  it  darkens  in  the  subsequent  operations.  As 
the  paper  has  about  the  same  sensibility  as  chloride  paper,  the  printing  occupies  con- 
siderably less  time. 


478         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

three  processes  for  special  consideration,  for  the  reason  that  they  have  them- 
selves created  somewhat  of  a  new  field  for  their  own  usefulness.  They  can 
hardly  be  considered  among  the  assassins,  though  it  may  be  they  would  not 
have  existed  but  for  the  hated  qualities  and  weaknesses  of  the  still  popular 
albumen  paper  printing  process.  I  refer  to  the  bromo-gelatiue  and  platinum 
processes. 

213.  The  bro mo-gelatine  paper  has  proven  the  most  popular  of  all  the 
printing  processes  after  albumen,  and  has  many  advantages,  though  it  will  not 
in  its  present  development  succeed  in  displacing  the  old  favorite. 

The  proofs  are  thrown  into  water,  which  is  to  be  renewed  until  the  whites  are  per- 
fectly colorless,  which  result  may  be  hastened  by  dilute  acetic  acid.  They  are  then  to 
be  toned  and  fixed  in  a  bath  of  sulphocyanide  of  ammonium,  to  which  a  little  chloride 
of  gold  has  been  added. — ED.  LIESEGANG. 

My  method  of  printing  upon  gelatine-chloride  paper  is  as  follows :  The  paper  is 
exposed  under  a  negative  to  ordinary  light  on  a  cloudy  day  for  a  few  seconds ;  the  light 
of  burning  magnesium  wire  immensely  diminishes  the  time  of  exposure. 

The  paper  is  then  softened  for  a  minute  in  clear  water,  after  which  it  is  treated  to  the 
developer,  formed  as  follows  : 

No.  1.  Neutral  oxalate  of  potash,  4  ounces;  neutral  citrate  of  potash,  1£  ounces; 
chloride  of  ammonium,  80  grains;  citric  acid,  120  grains;  distilled  water  or  water  from 
ice,  40  ounces. 

No.  2.  Protosulphate  of  iron,  480  grains;  water,  40  ounces;  sulphuric  acid,  10  drops. 

Fixing  bath:  Hyposulphite  of  soda,  4  ounces;  water,  20  ounces. 

Clearing  solution:  Water,  20  ounces;  pulverized  alum,  1  Jounces;  sulphuric  acid,  % 
ounce. 

Take  one  ounce  of  No.  1  and  one  ounce  of  No.  2  and  add  one  ounce  of  water;  pour 
over  the  paper  and  move  the  dish  as  in  ordinary  development.  The  image  will  very 
soon  begin  to  show  itself  and  develop  to  perfection.  If  the  paper  has  been  rightly 
timed,  a  beautiful  sepia  tone  will  be  produced  full  of  soft  and  rich  gradations ;  if  the 
time  has  been  a  little  full,  a  rich  russet-brown  is  the  result.  Delicate  purplish  tones  can 
also  be  secured  by  toning  the  print  with  gold,  as  with  an  ordinary  silver  print.  The 
tones  produced  by  the  development  alone  are  very  rich  and  pleasing,  but  if  the  purple 
tones  are  preferred,  with  the  use  of  the  gold  bath,  care  should  be  taken  thoroughly  to 
wash  out  the  iron  from  the  paper  before  subjecting  it  to  the  bath,  otherwise  there  will 
be  an  unevenness  in  the  tone,  and  the  bath  will  be  ruined.  To  prevent  this,  all  that  is 
necessary  is  to  subject  it  to  the  clearing  solution  given  above;  let  it  lie  in  this  for  ten 
minutes,  then  wash  before  placing  in  the  fixing  bath,  where  it  should  remain  ten  minutes ; 
keep  the  prints  in  motion  in  the  hypo  solution  as  with  ordinary  silver  prints.  Wash 
after  removal  from  the  hypo  and  the  operation  is  complete. — JOHN  CARBUTT. 

213.  Development  is  accomplished  in  a  simple  and  cleanly  manner.  The  well-known 
oxalate  of  iron  developer,  in  a  slightly  modified  form,  is  being  found  the  most  suitable. 


PECULIAR    PRINTING    PROCESSES.  479 

Paper  coated  with  sensitized  gelatine  is  not  a  new  invention,  since  it  is  well 
known  that  Baldus,  twenty  years  ago,  made  experiments  with  paper  prepared 
with  iodized  gelatine.  This  was  slow ;  to-day  we  require  more  rapidity  in  the 
operation,  and  in  most  all  onr  preparations  bromide  has  taken  the  place  of 
iodide. 

In  1873,  Mawdsley  had  already  proposed  the  use  of  bromized  paper;  but, 
notwithstanding  his  advice,  the  experiments  made  with  it  were  unsuccessful, 
his  formulas,  and  especially  the  mode  of  preparation,  being  still  defective.  In 
1883,  Mr.  Lamy  gave  us  a  very  good  paper.  Morgan,  in  Paris,  has  had  good 
success,  contemporary  with  Roche  and  Eastman  in  America.  "Alpha" 
paper  is  an  English  production  of  the  same  character. 

On  permanent  bromide  paper  one  can  make  an  enlargement  from  a  card 
negative.  The  exposure  is,  say,  fifteen  seconds  in  diffused  light,  and  the  de- 
velopment, that  given  in  the  formulae  furnished  with  each  roll.  The  sensi- 
tiveness is  so  great  that  it  is  possible  in  a  few  seconds,  by  the  light  of  a  candle, 
to -obtain  by  contact  with  any  negative  whatever  a  very  good  print;  even 
moonlight  will  print  quickly. 

This  extreme  sensitiveness  has  been  utilized  by  science  in  divers  ways : 
medicine  uses  it  to  ascertain  the  presence  of  subtle  poisons,  observatories  to 
register  the  atmospheric  changes,  which  previously  it  had  not  been  possible  to 

Developer :  A.  Oxalate  of  potash,  8  ounces ;  hot  water,  24  fl.  ounces.  Make  acid  with 
acetic  acid  No.  8.  Test  with  blue  litmus  paper. 

B.  Anthony's  pure  iron,  8  ounces;  hot  water,  16  fl.  ounces;  sulphuric  acid,  C.  P.,  10 
minims. 

C.  Bromide  of  potassium,  1  ounce ;  water,  32  fl.  ounces. 

Note. — The  dry  measure  above  quoted  is  based  on  437  grains  to  the  ounce.  Keep  these 
solutions  separate ;  they  must  be  mixed  only  for  immediate  use. 

To  develop :  A,  3  ounces ;  B,  £  ounce ;  C,  10  minims. 

Mix  in  the  order  given;  use  cold.  After  exposure,  soak  the  paper  in  water  until 
limp ;  then  immerse  in  the  developer. 

The  image  should  appear  slowly,  and  should  develop  up  strong,  clear,  and  brilliant. 
When  the  shadows  are  sufficiently  black,  pour  off  the  developer  and  flood  the  print  with 
the  clearing  solution — Acetic  acid,  1  drachm;  water,  1  quart.  Do  not  wash  the  print 
after  pouring  off  the  developer  and  before  applying  the  clearing  solution. 

Use  a  sufficient  quantity  to  flow  over  the  print — say  2  ounces  for  an  8  x  10.  Allow  it 
to  act  for  one  minute,  and  then  pour  it  off  and  apply  a  fresh  portion ;  repeat  the  opera- 
tion a  third  time,  then  rinse  in  pure  water  and  immerse  for  ten  minutes  in  the  fixing 
bath— Hyposulphite  of  soda,  8  ounces ;  water,  40  ounces.— E.  &  H.  T.  ANTHONY  £  Co. 
,  After  fixing,  wash  thoroughly  for  two  hours  and  hang  up  to  dry.  Use  fresh  developer 


480         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

do,  etc.  ID  photography  it  is  certain  that  it  can  render  great  service  when  it 
is  necessary  to  produce  a  great  number  of  prints  in  a  short  space  of  time.  One 
can,  in  five  minutes,  produce  alone,  by  gaslight,  forty  prints  from  the  same 
negative.  The  gelatino-bromized  paper  is  placed  under  a  negative  in  the 
pressure-frame,  exposed  to  gas  or  any  other  light,  developed  with  oxalate  and 
iron,  then  fixed.  The  operation  lasts  between  five  and  six  minutes,  whatever 
may  be  the  number  of  prints. 

Thus  obtained,  these  prints,  although  strong,  have  the  softness  of  crayor 
drawings  together  with  photographic  delicacy  and  preciseness. 

For  enlargements,  the  gelatino-bromized  paper  has  considerable  vak  j. 
With  the  ordinary  processes  with  a  print,  or  even  small  negative,  several  diffi- 
cult operations  are  indispensable  to  obtain  an  enlarged  print.  First,  it  is 
necessary  to  print  by  contact  or  to  enlarge  slightly,  either  a  gelatino-bromized, 
or  chlorized  plate,  or  collodion  plate,  or  a  positive  by  transparency,  from  which 
is  obtained  a  large  negative  to  be  used  in  printing ;  finally,  the  enlargement, 
either  with  carbon  or  on  albumenized  paper.  With  gelatino-bromized  paper 
all  these  operations  are  done  away  with.  It  is  the  little  negative  itself  that 
gives  the  enlarged  picture. 

The  manufacture  of  this  paper  is  no  more  difficult  than  albumenizing. 
Three  grades  are  in  the  market : 

for  each  batch  of  prints.  With  a  glass-bottomed  tray,  seven  ounces  of  developer  are 
sufficient  for  a  25  x  30  print. 

The  clearing  solution  is  to  prevent  the  precipitation  of  the  iron  from  the  developer  in 
the  fibre  of  the  paper.  This  can  only  be  done  by  keeping  the  paper  acid  while  washing 
out  the  developer. 

Citric  acid  may  be  used  instead  of  acetic  in  the  clearing  solution,  in  which  case  use  | 
ounce  to  the  quart  of  water.  Citric  acid  is  less  liable  to  cause  blisters. 

Blisters  may  be  avoided  by  using  a  little  common  salt  in  the  first  washing  water  after 
fixing.  The  hypo  must  not  be  stronger  than  3  ounces  to  the  pint  of  water. 

The  final  tones  are  obtained  entirely  by  development,  and  range  from  a  soft  gray  to  a 
rich  velvety  black,  depending  somewhat  upon  the  density  of  the  negative  and  the  quality 
of  the  light  used  in  printing. 

The  faintest  trace  of  hyposulphite  of  soda  or  of  pyrogallic  acid  is  fatal  to  got>d  results 
with  bromide  paper,  and  the  operator  cannot  be  too  careful  to  avoid  any  contamination. 
The  tray  used  for  developing  with  oxalate  should  never  be  used  for  anything  else. 

Mention  has  been  made  in  these  directions  regarding  the  use  of  a  dilute  solution  of 
acetic  acid  and  water  immediately  after  development,  and  before  washing  with  water  at 
all.  Pure  whites  cannot  possibly  be  obtained  and  retained  where  this  precaution  is 
neglected. 

After  fixing,  another  important  measure  is  the  use  of  a  first  washing  water  containing 


PECULIAR    PRINTING    PROCESSES.  481 

Smooth  surface,  thin,  for  proofs,  positive  printing,  copying  drawings,  etc., 
by  contact. 

Smooth  surface,  heavy,  for  positive  printing,  enlarging,  and  working  in  ink, 
oil,  and  water  colors. 

Rough  surface,  heavy,  for  positive  printing,  enlarging,  and  working  in 
crayon,  ink,  water  colors,  and  oil. 

The  best  paper  is  uniformly  and  heavily  coated  by  machinery  with  silver 
bromide,  mixed  with  the  least  possible  quantity  of  gelatine  to  avoid  curling 
and  to  preserve  the  tooth  of  the  paper  for  working  with  crayons. 

The  rough  paper  is  recommended  for  plain  enlargements  and  contact  prints 
of  all  kinds,  on  account  of  the  fine  artistic  effects  to  be  obtained. 

From  good  original  negatives,  enlargements  may  be  obtained  that  require  no 
finishing. 

I  add,  condensed,  the  directions  given  by  the  makers : 

In  contact  printing  with  permanent  bromide  paper,  the  exposure  is  prefer- 
ably made  by  artificial  light,  to  insure  uniformity,  and  to  avoid  overexposure. 

Yellow  post-office  paper  is  the  best  medium  for  filtering  the  light  through 
for  working  permanent  bromide  paper;  two  thicknesses  should  be  used  for 
daylight  and  one  for  gas  or  kerosene. 

Permanent  bromide  paper  is  about  one-half  as  sensitive  as  a  collodion  wet 

common  salt — say  half  a  pound  to  two  gallons  of  water.  This  will  most  effectually  pre- 
vent blistering,  unless  provoked  by  some  unusually  careless  manipulation. 

Two  hours'  washing  in  ten  or  twelve  changes  of  water,  is  sufficient  to  remove  all  traces 
of  hypo,  and  the  prints  are  ready  for  mounting  immediately,  if  desired,  or  may  be  dried 
by  allowing  to  drain  on  a  screen  covered  with  cheese-cloth.  Mounting  on  muslin-covered 
stretchers  may  be  accomplished  either  wet  or  dry,  the  first  method  being  the  most  expe- 
ditious and  satisfactory.  This  is  conducted  as  follows :  Drain  your  print  of  all  surplus 
moisture,  and  lay  it  face  down  on  a  table,  over  which  is  thrown  smoothly  a  well  wetted 
sheet  of  rubber-coated  cloth ;  apply  the  paste  thoroughly  to  the  back,  paste  also  evenly 
and  without  lumps  over  the  face  of  the  muslin  stretcher.  If  the  print  is  accurately 
centred  on  the  sheet  of  paper,  the  mount  may  be  laid  on  it,  face  down,  and  rubbed  in 
contact  with  a  wad  of  soft  cloth,  care  being  taken  to  avoid  rubbing  too  close  to  the 
stretcher,  as  this  would  present  a  visible  outline  on  drying  and  mar  the  appearance  of 
the  print.  All  air  bubbles  being  carefully  pressed  as  nearly  toward  the  side  as  is  safe. 
Take  hold  of  the  stretcher  by  one  corner  and  lift  together  with  the  rubber  cloth ;  on 
dropping  the  latter,  it  will  leave  the  surface  of  the  print  without  resistance,  which  may 
be  placed,  face  up ;  and  with  the  palm  of  the  hand  wetted,  the  edges  can  be  brought 
into  perfect  contact.  Drying  may  be  hastened  by. exposure  to  a  current  of  air  in  a  well- 
ventilated  room. 

Mounting  on  cardboard  may  be  accomplished  in  a  somewhat  similar  manner.  The 

31 


482        WILSON'S  QUATTER  CENTURY  IN  PHOTOGRAPHY. 

plate,  or  one-twentieth  as  sensitive  as  a  good  dry  plate,  and  should  be  exposed 
accordingly. 

The  exposure  varies  with  the  intensity  of  the  negative  and  the  quality  and 
intensity  of  the  light,  but  may  be  approximately  stated  to  be,  using  as  thin  a 
glass  or  American  film  negative  as  will  make  a  good  print,  one-quarter  second 
by  diffused  daylight,  or  ten  seconds  at  a  distance  of  one  foot  from  a  No.  2 
kerosene  burner.  With  an  oiled  paper  negative  it  requires  twice  as  much  and 
with  an  unoiled  paper  negative  about  three  to  five  times  as  much  exposure. 
Very  thin  negatives  should  be  printed  by  weak  yellow  light,  like  that  obtained 
from  a  kerosene  lamp  turned  down  a  little  below  the  normal  intensity.  In 
this  way  a  strong,  vigorous  print  may  be  obtained  from  a  negative  that  would 
otherwise  be  too  thin  and  flat. 

The  Developer. — Formulae:  No.  1.  Oxalate  of  potash,  1  pound;  hot  water, 
48  ounces ;  acetic  acid,  3  drachms.  No.  2.  Protosulphate  of  iron,  1  pound ; 
hot  water,  32  ounces ;  acetic  acid  (or  citric  acid  J-  ounce),  J  drachm.  No.  3. 
Bromide  of  potassium,  1  ounce ;  water,  1  quart. 

These  solutions  keep  separately,  but  must  be  mixed  only  for  immediate  use. 

To  develop  :  Take  in  a  suitable  tray — No.  1,  6  ounces;  No.  2,  1  ounce; 
No.  3,  J  drachm. 

Soak  the  exposed  print  until  limp,  then  transfer  to  the  tray  containing  the 
developer,  taking  care  to  avoid  bubbles. 

print  is  pasted  lying  face  down  on  the  wetted  rubber  cloth ;  it  is  then  raised  and  centred 
on  its  mount  as  an  ordinary  mounting ;  the  only  precaution  necessary  is,  that  the  damp 
rubber  cloth  is  laid  down  on  the  face  of  the  prints,  and  with  a  squeegee  uniformly  and 
rapidly  moved  back  and  forth,  contact  is  assured.  Lift  the  rubber  cloth  by  one  end,  and 
the  mounted  print  will  fall  to  the  table  by  its  own  weight. — DAVID  COOPER. 

Failure  is  chiefly  due  to  utter  ignorance  of  a  certain  law  in  optics,  which  may  be  found 
stated  in  the  text-books  as  a  thing  which  must  be  digested  by  the  student,  but  which  is 
seldom  explained  in  a  rational  manner.  Here  is  the  law :  "  The  intensity  of  illumina- 
tion on  a  given  surface  is  inversely  as  the  square  of  its  distance  from  the  source  of  light." 
Let  us  see  whether  this  matter  cannot  be  explained  in  such  a  way  that  a  child  can 
understand  it,  and  turn  it  to  practical  use  in  photography. 

Referring  to  Fig.  370,  let  the  four  squares  numbered  1,  2,  3,  and  4,  be  printing-frames 
placed  at  distances  of  1,  2,  3,  and  4  feet  from  a  candle  flame.  Let  us  suppose,  also,  that 
we  have  ascertained  by  experiment  that  the  plate  or  paper  in  the  first  position  (No.  1)  is 
sufficiently  affected  by  the  light  if  it  remain  there  for  one  minute.  (Thjs  is,  of  course, 
merely  stated  as  a  case  in  point.  Bromide  paper  at  such  a  distance  would  be  sufficiently 
exposed,  under  a  normal  negative,  in  about  eight  seconds,  while  a  chloride  plate  under 
such  conditions  would  want  two  minutes  or  more.)  Then,  if  we  remove  the  frame  to 
position  No.  2,  at  two  feet  from  the  light  source,  the  necessary  exposure  will  not  be 
doubled,  as  some  might  think,  but  quadrupled.  For  the  square  of  2  is  that  number  mul- 


PECULIAR    PRINTING    PROCESSES. 


483 


The  image  should  appear  slowly,  and  should  develop  up  strong,  clear,  and 
brilliant.  When  the  shadows  are  sufficiently  black,  pour  off  the  developer 
and  flood  the  print  with  the  clearing  solution — Acetic  acid,  1  drachm  ;  water, 
32  ounces. 

Do  not  wash  the  print  after  pouring  off  the  developer  and  before  applying 
the  clearing  solution. 

Use  a  sufficient  quantity  to  flow  over  the  print,  say  2  ounces  for  an  8  x  10. 
Allow  it  to  act  for  one  minute  and  then  pour  it  off  and  apply  a  fresh  portion ; 
repeat  the  operation  a  third  time,  then  rinse  in  pure  water  and  immerse  for  ten 
minutes  in  the  fixing  bath — Hyposulphite  of  soda,  3  ounces ;  water,  16  ounces. 

After  fixing,  wash  thoroughly  two  hours,  in  at  least  twelve  changes  of  water 
and  hang  up  to  dry.  Use  fresh  developer  for  each  batch  of  prints.  With  a 
glass  bottomed  tray,  seven  ounces  of  developer  are  sufficient  for  a  25  x  30  print. 

The  object  of  the  clearing  solution  is  to  prevent  the  precipitation  of  the  iron 
from  the  developer  in  the  fibre  of  the  paper.  This  can  only  be  done  by  keep- 
ing the  paper  acid  while  washing  out  the  developer. 

Citric  acid  may  be  used  instead  of  acetic  in  the  clearing  solution,  in  which  case 
use  J  ounce  to  the  quart  of  water.  Citric  acid  is  less  liable  to  cause  blisters. 

If  a  matt  surface  is  not  satisfactory  the  prints  may  be  enamelled. 

No  toning  is  required.     All  the  points  accompany  each  roll  of  paper. 

tiplied  by  itself — i.  e.,  4.    The  right  exposure,  therefore,  will  be  four  minutes.    Removing 
the  frame  to  position  3,  we  must  once  more  square  that  number  in  order  to  arrive  at  the 

FIG.  370. 


right  number  of  minutes  for  exposure  at  this  increased  distance,  3X3=9.  Therefore 
nine  minutes  will  be  the  time.  It  is  easy  to  see  that  when  the  printing-frame  is  removed 
to  the  furthest  distance  of  all,  which  is  four  feet  from  the  light  source,  the  exposure  will 
be  increased  to  sixteen  minutes.  To  make  the  diagram  (Fig.  370)  more  explicit,  the 


484 


WILSON'S    QUARTER    CENTURY    IN    PHOTOGRAPHY. 


FIG.  371. 


For  enlarging,  an  easel  and  an  enlarging  camera  are  needful.  First,  the 
easel  (Fig.  371).  It  consists  of  a  firmly  supported  pair  of  uprights,  which  are 

slotted  a  distance  of  about  six  inches.  This 
admits  of  the  focussing-screen  being  moved 
up  and  down  so  as  to  locate  the  picture  cor- 
rectly in  the  centre  of  the  sheet.  On  the 
face  ot  the  board  is  the  black  frame  which 
is  hinged  on  one  side  and  caught  by  a  spring 
catch  on  the  other ;  its  object  I  will  describe 
in  its  order.  Seated  on  brackets  which  are 
screwed  to  the  back  of  the  focussing-board 
is  a  long  narrow  box  that  is  designed  to 
hold  the  sensitive  paper,  which  comes  wound 
on  a  paper  tube  that  slides  on  an  axle  jour- 
naled  on  the  box.  At  the  back  is  a  brake 
of  simple  construction  which  prevents  the 
paper  unwinding  faster  than  is  desired. 
This  box  is  perfectly  light-tight,  and  the 
dark-room  may  be  opened  after  use  without 
at  all  affecting  the  paper  if  kept  in  the  box 
closed. 

The  engravings  (Figs.  372,  375,  and  376) 
illustrate  forms  of  apparatus  for  exposing 
upon  bromo-gelatine  paper,  devised  by  Mr.  F.  C.  Beach,  whose  instructions  for 
use  are  added. 

vertical  squares  1,  2,  3,  and  4  have  been  so  subdivided  that  the  number  of  spaces  in  each 
indicates  the  number  of  units  of  exposure,  be  that  unit  a  second,  a  minute,  or  an  hour. 
The  same  rule  holds  good  for  enlarging  operations.  Thus,  supposing  that  we  are  work- 
ing with  a  magic  lantern,  and  that  the  necessary  exposure  at  one  foot  from  the  lens  is 
half  a  minute;  at  two  feet  the  time  will  be  two  minutes;  at  three  feet  four  and  a  half 
minutes,  and  so  on.  The  practical  worker  will  have  this  little  bit  of  theory  in  his  mind 
whenever  he  is  operating,  and  he  will  soon  prove  that  the  theory  holds  good. 

Another  help  in  enlarging,  which  will  be  found  useful,  is  a  little  piece  of  apparatus — 
if  it  can  be  dignified  by  that  expression — which  I  have  lately  made,  and  which  I  call  an 
exposing  gauge.  It  is  so  simple  in  construction  than  anyone  can  make  it  out  of  a  couple 
of  strips  of  cardboard.  The  arrangement  is  shown  in  Fig.  373.  The  size  of  the  gauge 
is  immaterial,  but  a  length  of  twenty  inches  will  be  found  convenient.  A  slip  of  card 
of  that  length,  and  about  one  inch  in  breadth,  is  cut  with  pointed  ends,  each  point 
having  a  hole  picked  in  it  as  shown.  By  these  holes,  and  with  the  assistance  of  a  couple 


PECULIAR    PRINTING    PROCESSES. 


485 


A  short  focus  lens  of  the  portrait  combination  type,  provided  with  a  dia- 
phragm of  an  inch  aperture,  produces  the  best  results. 


FIG.  372. 


The  negative,  with  the  film  side  toward  the  lens,  is  held  in  the  slide  in  an 
inverted  position,  and  is  slid  into  the  grooved  frame  upon  the  exterior  side  of 
the  partition,  as  shown.  This  arrangement  allows  different  sized  negatives  to 
be  quickly  and  easily  adjusted.  On  an  adjustable  shelf,  which  can  be  raised 
or  lowered,  are  located  the  ground-glass,  kerosene  lamp,  and  reflector.  The 
centre  of  the  lamp-flame  reflector,  negative,  and  the  lens  of  the  camera  should 
be  in  one  focal  line. 

of  drawing  pins,  the  contrivance  can  be.readily  attached  to  any  flat  surface  upon  which 
the  enlarged  image  from  the  lantern  is  focussed.     Placed  above  this  slip  is  another  piece 

FIG.  373. 


of  card  slightly  shorter,  and  with  a  round  hole  in  the  centre.  The  two  slips  are  bound 
together  with  strips  of  tape  glued  over  their  upper  and  lower  edges,  the  two  ends  being 
left  open,  like  a  sleeve,  for  the  reception  of  a  slip  of  paper,  like  that  shown  in  Fig.  373. 

FIG.  374. 


J*  I  at,  iris 


1 


Fig.  374,  as  indicated,  really  consists  of  two  slips  of  paper  gummed  together  end  to  end. 
One  is  sensitive  bromide  paper,  ten  inches  in  length,  which  has  been  spaced  out  into 
five  divisions,  and  marked  a,  b,  c,  d,  e,  with  an  aniline  ink  pencil.  The  other  part  is 


486         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

The  ground-glass  in  front  of  the  lamp  diffuses  the  light  equally  over  the 
negative;  an  ordinary  magic  lantern  condenser  may  be  used  in  place  of  the 
ground-glass,  thereby  materially  decreasing  the  time  of  exposure. 


FIG.  375. 


When  obtaining  a  focus  the  room  is  to  be  closed  to  all  outside  light,  except 
that  which  comes  through  the  lens,  and  the  enlarged  image  of  the  negative  is 
seen  very  distinctly  upon  the  ground-glass  of  the  focussing  board.  The  saddle 
is  moved  back  and  forth  until  the  correct  focus  is  obtained,  as,  for  instance, 
when  the  hair  of  the  head  or  the  pupil  of  the  eye  looks  sharp  and  distinct. 

Having  obtained  the  correct  focus  on  the  ground-glass  on  the  focussing 
board,  the  operator  covers  the  lens  with  a  cap  of  ruby  glass,  turns  the  ground- 
glass  end  of  the  focussing  board  up,  and  fastens  on  the  lower  portion,  in  proper 
position,  the  sensitive  sheet.  When  the  sheet  is  rightly  located  the  hook  may 
be  unlatched  and  the  board  turned  flat,  as  shown,  so  that  the  paper  may  be 
more  easily  pinned  to  the  face  of  the  board  ;  the  latter  is  again  raised,  secured, 

ordinary  white  cartridge  paper,  slightly  longer  than  the  sensitive  slip.  Its  purpose  is  to 
serve  as  a  handle  by  which  to  pull  the  sensitive  paper  through  the  sleeve,  and  also  to 
furnish  a  white  surface  upon  which  a  small  part  of  the  picture  can  be  focussed,  that 
small  part  being  confined  to  the  central  circular  hole  in  the  upper  card. 

Now  let  us  see  how  the  gauge  is  used  in  practice.  It  is  first  pinned  on  the  focussing 
board  so  that  a  distinctive  part  of  the  image  is  thrown  upon  the  central  hole.  In  the 
case  of  a  portrait  this  should  be  the  eye.  Having  focussed  carefully  on  the  blank  paper, 
the  first  division  of  the  sensitive  slip,  which  will  be  that  marked  e,  is  pulled  in  front  of 
the  opening.  Let  this  be  exposed  for,  say,  fifteen  seconds,  then  pull  the  slip  onward  and 
expose  d  for  twenty  seconds,  c  for  twenty-five  seconds,  and  so  on.  The  gauge  is  then 
taken  into  the  dark-room,  its  slip  of  sensitive  paper  torn  from  its  yoke-fellow,  and  care- 
fully developed.  It  will  then  soon  be  seen  which  of  the  lettered  spaces  has  received  the 
correct  exposure ;  and  a  memorandum  noting  time  and  distance  of  lens  from  screen  can 
either  be  attached  to  the  negative  or  entered  in  a  book  against  a  number  corresponding 
with  a  number  scratched  on  the  glass  negative. 

The  same  principle  can  be  applied  to  printing  in  the  printing-frame  on  bromide  paper 
by  gas  or  lamplight.  When  the  frame  has  been  charged  with  its  negative  and  bromide 
paper,  support  it  upright  at  a  distance  of,  say,  eighteen  inches  from  the  turned-down 
flame.  Now,  place  in  front  of  it  an  opaque  card,  sufficiently  large  to  cover  more  than 


PECULIAR    PRINTING    PROCESSES.  487 

and  made  ready  for  the  exposure.    As  a  vignetted  picture  is  the  most  pleasing, 
and  can  be  easily  made,  the  operator  needs  to  provide  before  exposure  a  card- 


FIG.  376. 


board  having  a  notched  oval  aperture,  which,  during  the  exposure,  is  held 
between  the  lens  and  focussing  screen,  as  shown.  Looking  upon  the  screen  the 
dull-red  enlarged  image  may  now  be  seen,  but  the  moment  the  exposure  is 
made  by  removing  the  red  cap  from  the  lens,  the  picture  becomes  suddenly 
bright  and  brilliant.  The  operator  then  moves  the  vignetting  card  to  and 
from  the  exposed  sheet,  thereby  decreasing  and  enlarging  the  vignetting  circle. 

the  frame.  This  card  should  have  a  hole  about  one  inch  in  diameter  cut  in  it  in  one 
corner.  Turn  up  the  light  and  expose  for  five  seconds.  Alter  the  position  of  the  hole 
and  give  ten  seconds,  and  so  on.  When  the  paper  is  subsequently  developed  these 
several  exposures  can  be  readily  identified,  and  the  negative  can  be  labelled  to  the  effect 
that  it  requires  so  much  exposure  at  a  given  distance  from  a  flame.  Thus,  bromide 
paper,  18  in.  25  sec.  This  negative  will  then  be  an  infallible  guide  for  the  exposure  of 
negatives  of  a  similar  type ;  for  a  systematic  worker — unless  he  be  quite  a  beginner — 
will  fall  into  the  way  of  producing  negatives  of  much  the  same  character  and  strength, 
and  printing  from  them  by  lamplight  will  then  become  an  easy  matter  to  him. — DEXTEK, 
in  The  Camera. 


488         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

In  this  way  the  beautiful  soft  blending  so  characteristic  of  vignetted  pictures 
is  easily  produced.  With  a  lamp  like  a  No.  3  Leader  kerosene  burner,  giving 
a  flame  about  three  and  a  half  inches  wide  by  an  inch  and  a  half  highland  of 
about  twenty-six  candle  powder,  an  exposure  of  four  minutes  has  been  found 
sufficient.  The  exposure  may  be  quickly  stopped  by  replacing  the  red  cap  on 
the  lens. 

214.  The  platinotype  printing  process,  though  not  a  new  one,  has  not  had 
the  attention  it  deserves.  At  first  it  was  hampered  by  patents,  but  now  the 
inventors  are  content  to  derive  what  revenue  they  expect  from  their  processes 
by  selling  the  properly  prepared  material  to  their  licensees. 

An  exhaustive  paper  on  platinotypes  was  published,  after  much  industrious 
experiment,  by  Captain  Pizzighelli  and  Baron  A.  Hubl,  of  Vienna.  The 
practical  workings  of  the  method  as  detailed  by  them  are  given  below.  Of 
platinotype,  these  gentlemen,  after  giving  full  credit  to  Mr.  W.  Willis,  Jr., 
for  its  invention,  write  as  follows : 

"The  chief  advantages  of  this  process  are  (1)  the  simple  nature  of  the 
manipulation,  which  can  be  carried  out  much  more  plainly  and  readily  than  in 
any  other  printing  process ;  (2)  the  great  sensitiveness,  to  which  attention  has 
been  already  drawn  ;  (3)  the  perfect  permanence  of  the  prints  ;  (4)  the  peculiar 
character  of  the  pictures,  which,  from  an  art  point  of  view,  give  them  a  much 
higher  value  than  belongs  to  silver  prints.  Owing  to  the  exceeding  sensitive- 
ness of  the  platinum  process,  from  three  to  four  times  as  many  prints  may  be 

214.  Printing  the  Picture. — Printing  by  the  platinum  process  requires  greater  care  than 
in  silver-printing,  because  the  actinic  impression,  although  distinct,  is,  comparatively 
speaking,  only  faintly  visible.  It  is  necessary  to  get  accustomed  to  controlling  the 
progress  of  the  printing  operation  ;  but  the  experience  for  this  purpose  is  acquired  after 
a  few  trials.  By  the  action  of  the  light,  the  yellow  color  of  the  paper  becomes  changed 
to  brown,  and  after  longer  exposure  this  again  turns  of  a  lighter  shade,  so  that  often  the 
deepest  shadows  appear  lighter  than  the  darker  half-tones. 

Accurate  instructions  as  to  the  time  required  for  printing  can,  of  course,  not  be  here 
given,  as  it  depends  entirely  on  the  density  of  the  negative  and  on  the  conditions  of 
light  prevailing  at  the  moment.  We  can,  however,  state  with  certainty  that  platinum 
paper  is  at  least  three  times  as  sensitive  as  silver  paper,  and  that  this  greater  sensitive- 
ness makes  itself  more  felt  in  dull  than  in  bright  weather.  This  is  owing  to  the  greater 
sensitiveness  of  ferric  oxalate  to  the  less  refrangible  rays  of  the  spectrum.  For  a  good 
portrait  negative  of  average  intensity,  we  gave  from  twenty  to  twenty-five  minutes  with 
a  clear  sky  in  April ;  with  a  thinner  negative  we  printed  for  fifteen  minutes.  When  the 
prints  have  been  taken,  and  it  is  not  desired  to  develop  them  at  once,  they  are  kept,  as 
already  described,  in  a  chloride  of  calcium  box. 


PECULIAR    PRINTING    PROCESSES.  489 

taken  in  the  same  time  as  is  possible  with  the  silver  process.  This  advantage 
should,  as  we  have  already  pointed  out  in  the  introduction,  be  appreciated  in 
dull  weather,  more  especially  in  winter-time,  when  printing  by  the  silver 
process  is  nearly  impossible. 

"  After  being  printed,  the  pictures  can  be  completely  finished  in  half  an  hour, 
and  are  then  ready  to  be  mounted.  All  the  wearisome  washing,  toning,  fixing, 
and  again  washing,  which  are  necessary  for  silver  prints,  are  dispensed  with  in 
the  platinum  process,  and  the  great  care  which  must  be  taken  to  obtain  good 
results  by  the  former  is  quite  unnecessary  in  the  latter  process.  Only  very 
careless  treatment  causes  the  picture  to  be  spoiled.  For  producing  platinum 
prints  only  one  operation — that  of  sensitizing — requires  any  degree  of  atten- 
tion; while  for  silver  prints,  time,  trouble,  and  care  must  all  be  given  to 
obtain  pictures  which,  after  all,  are  only  of  doubtful  permanence.  When  we 
take  into  consideration,  also,  that  if  silver  prints  are  not  washed  with  extreme 
care  and  attention  they,  in  a  short  time,  are  quite  spoiled,  while  a  mistake  in 
the  same  direction  with  platinotypes  is  of  no  importance,  we  cannot  fail  to  see 
the  great  advantage  which  platinum  prints  possess  over  those  in  silver." 

215.  With  such  high  recommendation,  platinotype  printing  is  bound  to  find 
a  useful  place.  Nothing  can  be  more  soft  and  beautiful  than  its  results. 

215.  Developing  the  Picture. — To  develop  the  picture  we  take  a  saturated  (in  the  cold) 
solution  of  potassium  oxalate,  acidulated  with  oxalic  acid.     For  heating  the  solution  we 
may  employ  either  a  glass  boiling-flask  or  a  vessel  of  enamelled  iron  ;  but  this  supposes 
that  only  a  small  number  of  pictures  of  moderate  size  are  to  be  developed  in  a  basin  by 
pouring  the  solution  over  them.     When  they  are  of  large  size  and  in  greater  number 
this  method  would  not  answer,  as  the  solution  cools  by  being  poured  over  the  picture, 
and  therefore  will  have  to  be  heated  afresh.     In  this  case  we  prefer  to  use  a  vessel  of  flat 
or  bent  enamelled  iron  of  the  same  width  as  the  picture,  which  can  be  placed  over  a 
water  bath.     The  section  of  a  developing-tray  of  this  kind  is  shown  in  Fig.  377 ;  A  is  the 
enamelled  iron  vessel,  containing  the  oxalate  solution,  a  its  cover 
of  zinc  plate;  B  is  another  hollow  vessel,  with  double  wall  of  zinc 
plate,  which  acts  as  the  water  bath ;  C  is  a  gas  or  spirit  lamp.   The       ^ — ~ 
vessel  B  is  filled  with  hot  water  through  a  tube  let  into  the  upper 
side,  and  the  hot  solution  of  oxalate  is  then  poured  into  the  tray  A ; 
it  can  readily  be  kept  at  the  required  temperature  by  means  of  the 
lamp  underneath.     To  develop  it,  each  print  is  taken  separately 
by  two  opposite  sides   and  drawn  slowly  through  the  solution. 
Development  takes  place  at  once,  the  brown  color  changing  im- 
mediately to  a  deep  black.     If,  by  chance,  any  part  of  the  picture  does  not  come  in 
contact  with  the  solution — as,  for  instance,  where  any  air-bells  adhere  to  it — it  must  "be 
again  drawn  through  the  solution.     When  there  is  danger  of  the  print  having  been  too 


490        WILSON'S  QUAKTER  CENTURY  IN  PHOTOGRAPHY. 

Moreover  its  operations  hold  a  fascination  which  make  it  a  great  favorite  with 
printers.  Those  who  are  artists  claim  that  no  matt  surface  process  yields  so 
near  their  ideal  of  what  is  "  artistic  as  does  the  platinum  print,  and  therefore 
it  is  a  particular  favorite  with  them. 

long  copied,  a  somewhat  cooler  solution  of  potassium  oxalate  may  be  used,  though  the 
hot  solution  always  works  best.  The  temperature  of  80°  C.,  as  given  above,  may  be 
exceeded  when  the  print  has  been  copied  for  too  short  a  time;  we  have  ourselves  very 
often  employed  a  developing  solution  in  a  boiling  state. 

Finally,  we  would  again  direct  attention  to  the  necessity  of  having  always  an  acid 
reaction  in  the  developer.  When  the  solution  is  kept  continuously  at  a  high  tempera- 
ture, it  may  happen  that  the  evaporation  will  cause  crystals  of  potassium  oxalate  to 
form,  which  will  be  deposited  on  the  sides  of  the  vessel ;  those  being  over-heated  will 
partially  decompose  and  form  potassium  carbonate,  so  that  in  certain  circumstances  the 
solution  will  become  alkaline.  It  is,  therefore,  imperatively  necessary  to  keep  testing 
the  liquid  from  time  to  time  with  litmus  paper,  and,  if  necessary,  to  acidulate  the 
developer  with  oxalic  acid. 

After  being  used,  the  developing  solution  may  be  poured  back  into  a  flask,  and  can  be 
employed  again.  The  water  which  has  evaporated  should  occasionally  be  replaced,  and, 
as  often  as  necessary,  fresh  potassium  oxalate  should  be  added. 

Finishing  the  Picture. — Directly  the  picture  is  developed  it  must  be  immersed  in  a 
solution  of — Hydrochloric  acid,  1  part ;  water,  80  parts ;  and  left  there  until  any  of  the 
iron-salt  still  present  has  been  removed.  This  solution  of  hydrochloric  acid  must  be 
changed  (twice  or  three  times)  until  it  no  longer  turns  yellow.  We  ourselves  generally 
change  the  solution  three  times,  and  leave  the  print  in  it  each  time  for  about  ten 
minutes. 

Finally,  the  print  should  be  laid  for  a  short  time  in  a  pan  of  water  in  order  to  remove 
the  hydrochloric  acid ;  ten  to  fifteen  minutes  will  suffice  for  this  purpose.  Should  any 
hydrochloric  acid  remain  in  the  paper,  it  would  not  have  any  bad  effect  on  trie  print 
itself,  but  might  injure  the  substance  of  the  paper,  so  that  in  the  course  of  time  it  would 
be  destroyed.  To  be  perfectly  easy  on  this  point,  it  may  be  advisable  to  try  the  last 
wash-water  with  litmus  paper,  whether  it  comes  off  quite  neutral. 

After  washing,  the  picture  is  dried  in  the  ordinary  way,  and  can  then,  if  desired,  be 
mounted  on  cardboard.  Prints  on  smooth  paper  may  be  hot-pressed,  to  give  them  a 
slight  sheen,  which  brings  up  the  deep  parts. 

Prints  on  wood  or  linen  are  treated  just  the  same  as  those  on  paper.  As  the  plates  of 
wood  are  very  liable  to  warp,  through  being  moistened  with  the  sensitizing  solution  and 
then  heated  to  dry,  they  should  be  fastened  by  small  points  or  drawing-pins  flat  on  a 
strong  board.  Linen  can  be  kept  stretched  on  wooden  frames  after  being  coated  with 
the  sensitizer. 

At  this  stage  we  ought  further  to  point  out  that  platinum  prints  in  a  wet  state  appear 
always  more  brilliant  and  lighter  than  they  do  when  dry.  A  print,  therefore,  which 
while  still  wet  after  development  seems  to  be  quite  right  as  regards  tone,  would  be  too 
dark  when  dried.— PIZZIGHELLI  and  HTJBL. 


PECULIAR    PRINTING    PROCESSES.  491 

216.  Rapid  and  inexpensive  methods  for  reproducing  maps,  drawings,  proofs, 
and  other  emergent  pictures,  have  been  practised  for  a  long  time,  the  one 
known  as  the  "  blue  "  process  being  the  most  in  use. 

It  has  been  published  many  times  and  is  given  again  in  the  notes. 

Mr.  C.  G.  Busch,  a  practical  and  valued  friend,  has  given  me  a  modification 
which  I  have  the  privilege  of  including  here.  He  says  : 

"  I  have  been  experimenting  to  make  my  owrn  blue  paper,  and  I  enclose  a 
few  blue  prints  made  on  this  paper.  The  best  result  I  get  in  the  following 
way  :  I  make  out  of  the  stick  ing-paper  which  is  sold  by  the  roll,  four  loops 
one  inch  long,  fasten  these  on  each  corner  of  a  sheet  I  wish  to  paint,  put 
through  those  loops  a  thread — of  wool  is  best,  it  does  not  cut  through  the  loop 
so  easily — and  put  a  little  weight  on  the  end  of  each  string,  to  hang  down  over 
the  table  I  want  to  use  to  paint  the  sheet.  This  is  for  keeping  it  in  place,  and 
by  stretching,  to  remain  flat.  I  use  a  fine  camel's-hair  brush  about  If  to  2 
inches  wide.  Put  into  a  dish  2  drachms  of  water  and  let  the  brush  fill  with 
water,  besides  the  2  drachms,  which  is  also  a  drachm  or  a  little  more.  I  brush 
these  2  drachms  of  water  on  to  the  sheet  as  uniformly  as  possible,  by  taking  it 

216.  The  "blue"  process  is  most  used  in  America,  and  has  been  largely  adopted  by 
our  manufacturers.  The  drawings  are  reproduced  in  white  lines  on  a  blue  ground,  and 
I  understand  the  paper  is  sold  in  the  market  already  sensitized,  although  it  can  be  pre- 
pared cheaper  and  just  as  well  as  the  bought  article.  Almost  any  heavy  well-glazed 
printing  paper  will  answer  the  purpose,  but,  as  this  is  the  only  expense,  a  good  quality 
should  be  used.  The  sensitizing  bath  consists  of  (a)  Citrate  of  iron  and  ammonia,  1  part ; 
clear  water,  4  parts.  (6)  Red  prussiate  of  potash,  1  part;  water,  6  parts. 

The  two  solutions  are  dissolved  separately,  and  preferably  at  the  ordinary  temperature ; 
when  in  complete  solution  they  are  mixed,  and  kept  in  a  yellow  bottle,  or  carefully  ex- 
cluded from  the  light,  which  would  cause  a  blue  precipitate.  If  the  paper  is  not  suf- 
ficiently sized,  gum  or  gelatine  should  be  added  to  give  it  body  and  prevent  the  liquid 
from  soaking  through.  The  sensitizing  is  performed  as  follows,  in  non-actinic  light: 
The  sheet  of  paper,  cut  to  the  required  size,  is  pinned  to  a  clean  board;  some  of  the 
solution  is  poured  into  a  vessel,  and  the  paper  painted  with  it  by  means  of  a  soft  camel's- 
hair  brush  three  inches  wide.  The  brush  is  dipped  into  the  solution  and  the  paper 
completely  moistened  in  one  direction ;  then,  without  removing  the  liquid,  it  is  smoothed 
until  no  streaks  or  lines  appear.  Some  prefer  to  use  a  sponge,  but  this  causes  uneven 
spots,  and  mars  the  beauty  of  the  picture.  In  this  way  a  very  little  solution  will  cover 
quite  a  large  surface.  Before  putting  the  brush  away  it  must  be  carefully  cleaned.  The 
paper  is  unpinned,  hung  upon  a  line,  and  when  dry  will  keep  a  long  time  in  the  dark. 
It  should  be  a  brass-yellow  color  when  rightly  prepared.  To  make  a  copy,  the  drawing, 
on  tracing  cloth,  is  put  into  the  printing  frame,  as  usual,  with  a  sensitive  sheet,  and 
exposed  to  sunlight  for  six  to  ten  minutes,  or  to  diffused  light  for  one  to  two  hours.  The 


492         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

up  in  at  least  six  to  eight  times.  The  sheet  is  pretty  well  saturated  now.  I 
have  two  solutions :  No.  1  is  If  ounces  of  citrate  of  iron  and  ammonia  in  8 
ounces  of  water;  Xo.  2  is  1^  ounces  of  red  prussiate  of  potash  in  8  ounces  of 
water ;  or  both,  if  less  is  wanted,  in  proportion.  Take  of  each  of  the  solutions 
f  to  1  drachm,  mix,  and  brush  on  the  wetted  sheet  as  evenly  as  possible  in  all 
directions ;  bear  on  very  lightly,  and  take  it  up,  say,  six  to  eight  times.  Now 
your  brush  contains  a  very  strong  solution.  Put  1  more  drachm  of  water  in 
the  dish  and  work  it  up,  and  after  this  add  J  drachm  more  water ;  there  will 
be  now  a  very  weak  solution  in  the  brush.  If  you  want  to  do  more  than  one 
sheet,  I  would  advise  two  brushes  and  two  dishes  to  use,  one  for  wetting  and 
the  other  for  putting  on  the  solution.  If  you  do  so,  }  drachm  of  each  solution 
for  each  sheet  is  just  right  and  enough.  By  examining  the  print  during  print- 
ing, the  details  show  up  very  nicely,  almost  as  a  silver  print.  Too  much  of 
the  solution  put  on  makes  it  only  harder  for  you  to  see  if  the  print  is  done 
or  not. 

"  The  paper  prints  the  quickest  fresh,  but  the  most  delicate  tones  are  obtained 

double  salt  is  reduced  to  the  ferrous  state  where  the  light  strikes  it,  and  immediately 
combines  with  the  red  prussiate  present  to  form  Turnbull's  blue,  while  the  protected 
parts  remain  unchanged.  The  exposure  should  be  continued,  until,  on  opening  the 
frame,  the  white  lines  have  almost  disappeared  and  the  background  is  grayish-green. 
The  sheet  may  also  be  exposed  on  a  board  padded  with  flannel,  over  which  is  placed  a 
sheet  of  plate-glass,  but  this  requires  to  be  always  horizontal,  and  needs  more  apparatus 
than  it  would  cost  to  get  a  regular  frame.  When  exposure  is  finished  the  print  is  removed, 
and  put*  immediately  into  a  tank  of  running  water,  when  the  lines  will  become  white 
(unless  overexposed  or  not  in  contact),  while  the  ground  becomes  dark  blue.  After  suf- 
ficient washing,  the  ground  can  be  improved  by  transferring  to  a  bath  of  hydrochloric 
acid,  5  parts;  water,  100  parts;  when  it  must  be  again  thoroughly  washed,  and  then 
dried.  The  color  always  darkens  on  drying,  and  prints  that  would  otherwise  be  under- 
exposed have  very  beautiful  light-blue  ground. 

This  process  has  become  the  favorite  one,  owing  to  its  great  simplicity,  and  the  ease 
with  which  any  one  can  work  it;  the  objections  to  it  are:  the  length  of  exposure,  espe- 
cially on  cloudy  days,  and  the  impossibility  of  copying  drawings  from  anything  but  tracing 
cloth  or  paper.  In  very  large  sheets  the  fine  lines  are  apt  to  be  reduced,  thus  making 
the  picture  somewhat  uncertain  in  parts.  If,  instead  of  mixing  the  solutions,  the  paper 
had  been  sensitized  with  the  citrate  bath  and  then  exposed,  the  reduction  would  have 
been  very  rapid  (fifteen  or  thirty  seconds),  as  this  is  the  most  sensitive  salt  of  iron.  The 
picture  could  then  be  developed  in  the  ferricyanide  bath,  and  finished  as  described  ;  but 
in  this  case  it  is  better  to  sacrifice  sensitiveness  to  convenience.  The  other  double  salts 
could  be  used  to  replace  the  citrate,  but  they  require  a  longer  exposure. — DAVID 
TOWNSEND. 


PECULIAR    PRINTING    PROCESSES.  498 

when  it  is  a  week  or  ten  days  old.  It  requires  more  time  then,  but  the  de- 
tails are  better  By  this  method  I  think  the  sensitive  material  lies  in  more 
compact  form  on  the  surface,  than  if  floated  or  put  on  without  wetting  the 
sheet. 

217.  A  white  line  on  a  blue  ground  is  not  so  pleasing  to  the  eye  as  the 
reverse  would  be,  and  a  goodly  amount  of  ingenuity  has  been  expended  to  dis- 
cover methods  which  would  be  as  simple  and  easy  as  the  "  blue "  and  more 
pleasing  in  appearance.  Among  the  most  practical  are  Willis's  aniline  process, 
the  gallate  or  tannate  of  iron  process,  cyanotype,  and  the  varied  uses  of  salts 
of  iron. 

In  addition  to  what  are  mentioned,  there  is  the  "  powder "  process.  It  is 
hardly  desirable  enough  to  give  in  full. 

One  of  the  best  has  been  given  by  Dr.  J.  H.  Janeway,  U.  S.  A.  It  is 
named  after  the  deceased  inventor — a  friend  of  his — "  the  Powell  print." 

His  process  is  as  follows :    He  passes  any  good,  hard,  sized  paper  suitable 

217.  The  details  of  the  aniline  process  I  use  are  as  follows  : 

1.  Sensitizing. — The  best  paper,  Saxe  preferred,  must  be  used,  as  nothing  else  will  give 
satisfactory  results.     The  sensitizing  solution  consists  of  bichromate  of  potassium,  1  part  ; 
phosphoric  acid,  sp.  gr.  1.124,  8-10  parts;  water,  10-12  parts. 

The  paper  is  cut  to  size,  and  then  fastened  with  pins  to  a  clean,  flat  board.  Some  of 
the  solution  is  poured  into  a  dish,  and  the  paper  is  sensitized  by  means  of  a  stiff  brush 
about  one  inch  wide,  which  is  dipped  into  the  liquid,  and  then  painted  on  paper,  first 
lengthwise  and  then  across,  without  removing  the  liquid  in  the  brush.  Finally,  a  soft 
camel's-hair  duster,  three  inches  wide,  is  used  to  remove  all  superfluous  liquid,  and 
smooth  out  any  streaks  left  by  the  first  brushing.  The  solution  can  also  be  applied  with 
a  soft  sponge,  but  I  prefer  the  first  method,  as  the  fingers  are  then  not  brought  into  con- 
tact with  the  bichromate,  which  is  a  violent  poison. 

The  sheet  is  now  hung  up,  and  allowed  to  dry  slowly,  it  being  complete  in  from  fifteen 
to  twenty  minutes.  This  operation  should  be  performed  in  a  dark-room,  such  as  is  used 
for  wet  plates,  owing  to  the  extreme  sensitiverfess  of  the  paper,  which  is  easily  spoiled 
by  the  least  actinic  light.  When  dry,  the  paper  may  be  exposed  at  once,  or  kept  in  a 
dark  place  unaltered  for  a  long  time.  The  brushes  should  be  thoroughly  washed  and 
dried  after  each  time  they  are  used 

2.  Exposing. — The  prepared  paper  is  now  put  in  the  printing- frame  under  the  tracing, 
covered  with  a  black  cloth,  and  carried  into  the  sunlight.     The  time  of  exposure  will 
vary  with  the  time  of  the  year,  in  summer  being  about  twenty  to  twenty-five  seconds, 
and  in  winter  forty  to  forty-five  seconds.     The  surest  method  is  to  use  Vogel's  photo- 
meter, and  carry  the  exposure  to  sixteen  degrees,  but  if  the  instrument  is  not  handy, 
experiments  will  have  to  be  made  to  determine  the  exposure. 


494         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

for  the  cyanotype  picture  through  a  bath  of  dilute  gelatine,  which  he  prepared 
as  follows :  Two  and  a  quarter  grains  of  gelatine  to  each  ounce  of  water ;  after 
passing  the  paper  through  the  gelatine  bath  it  is  hung  up  to  dry  and  drain, 
using  all  precautions  to  avoid  unevenness  of  coat,  streaks,  and  marks ;  when 
quite  dry  the  sized  paper  should  be,  in  the  dark,  evenly  coated  with  a  solution 
composed,  say,  of  seventy  grains  of  ammonio-citrate  of  iron,  with  sixty  grains 
of  ferridcyanide  of  potash  in  two  ounces  of  water,  which  should  be  prepared 
and  kept  in  the  dark.  This  is  then  the  prepared  paper,  which,  when  duly 
exposed  under  a  negative  to  light,  may  produce  the  variety  of  image  desired. 
When  printed  it  is  washed  in  two  or  three  changes  of  clear  water,  and  we  have 
the  developed  print  no  longer  sensitive  to  light.  This  print  needs  now  only 
to  be  blotted  off  from  superfluous  water,  when  it  is  ready  for  immersion  in  the 
discharging  bath.  The  discharging  bath  may  be  composed  of  a  variety  of 
agents,  such  as : 

Here  is  the  most  important  part  of  the  whole  process,  because  underexposure  will  not 
reduce  the  bichromate  sufficiently,  and  overexposure  renders  the  paper  less  liable  to 
form  aniline  colors.  When  the  paper  is  rightly  prepared,  it  should  be  of  a  yellow  color, 
and  after  exposure  on  opening  the  frame,  a  faint  yellow  picture  will  be  observed  on  a 
greenish  ground. 

3.  Fuming. — When  the  exposure  is  judged  sufficient  the  cloth  is  replaced,  and  the 
frame  carried  back  into  the  dark-room,  where  it  is  opened,  the  picture  removed,  and 
pinned  to  the  lid  of  a  fuming-box.     The  box  is  provided  with  a  sheet  of  glass,  on  which 
is  blotting-paper  soaked  with  a  solution  of  aniline  oil,  1  part,  benzine,  10  parts,  and 
which  can  be  lowered  or  raised  at  pleasure  by  means  of  crosspieces  of  wood  at  different 
heights.     It  is  allowed  to  remain  for  thirty  minutes,  when  the  picture,  if  rightly  exposed, 
will  be  sufficiently  developed,  and  will  show  dark  brown  to  black  on  a  grayish  ground. 
If  the  image  be  rather  faint,  it  should  be  allowed  to  remain  for  two  or  three  hours  longer. 

4.  Washing. — On  taking  out  the  print,  it  must  be  washed  for  some  time  in  at  least  four 
changes  of  clean  water,  when  the  colors  will  be  sufficiently  fixed,  and  after  drying  the 
picture  is  finished. 

Great  care  must  be  taken  not  to  handle  the  sensitive  paper  any  more  than  is  absolutely 
necessary,  and  then  only  with  perfectly  clean  hands;  also  to  perform  all  the  operations  in 
absolutely  non-actinic  light.  With  these  precautions,  I  think  success  may  be  assured. — 
DAVID  TOWNSEND. 

Prints  with  gallate  or  tannate  of  iron,  giving  directly  positives  in  black,  of  a  drawing 
or  of  a  positive  cliche,  are  made  as  follows : 

The  process,  which  is  also  called  heliography,  is  very  simple,  easy,  and  inexpensive ; 
it  gives  halftones,  and  the  prints  made  by  it  are  ink-black  and  directly  positive  from  a 
positive  or  negative  from  a  negative. 

We  owe'this  process  to  Mr.  Poitevin,  but  it  has  been  slightly  improved. 


PECULIAR    PRINTING    PROCESSES.  495 

(A)  The  carbonate,  bicarbonate,  sesquicarbouate  of  soda. 

(B)  The  soluble  alkaline  silicate  of  potash  and  soda. 

(C)  Biborate  of  soda,  known  as  borax. 

Any  of  the  above  reagents  dissolved  in  the  proportion  of  ten  grains  to 
the  ounce  of  water  will  discharge  the  color  of  the  "  blue  print/7  still  leaving 
the  salt  of  iron  in  the  form  of  a  nearly  invisible  and  perfect  image  on  the 
paper. 

He  preferred  to  combine  the  discharging  bath  of  ten  grains  of  efflorescent 
sesquicarbonate  of  soda  with  each  ounce  of  water.  In  this  bath  immerse  the 
"  blue  print "  till  the  color  is  discharged  and  the  paper  loses  nearly  all  trace 
of  the  picture,  except  a  rusty  color  more  or  less  distinctly  marked  with  the 
image  in  the  strong  shadows.  When  the  blue  color  has  vanished  in  the  dis- 
charging bath  the  paper  is  washed  in  two  or  three  changes  of  clear  water  and 
is  then  blotted  off  to  remove  any  remaining  traces  of  soda  salts,  which,  if  left 
in  the  print,  would  modify  final  color.  The  print  is  now  discharged  and  ready 
for  the  toning-bath,  for  which  we  may  employ  gallic,  tannic,  or  pyrogallic  acid, 

A.  Sensitizing  solution:  Dissolve  separately — 1.  Gum  arabic,  13  drachms;  water,  17 
ounces.     2.  Tartaric  acid,  13  drachms ;   water,  6  ounces  6  drachms.     3.  Persulphite  of 
iron,  8  drachms;  water,  6  ounces  6  drachms. 

The  third  solution  is  poured  into  the  second,  well  agitated,  and  then  these  two  solu- 
tions united  are  added  to  the  first,  continually  stirring.  When  the  mixture  is  complete, 
add  slowly,  still  stirring,  100  c.  c.  (3  fl.  oz.  3  drms)  of  liquid  acid  perchloride  of  iron  at 
45°  Baume.  Filter  into  a  bottle  and  keep  away  from  the  light.  It  keeps  well  for  a  very 
long  time. 

B.  Sensitizing  the  paper :    Here  especially  it  becomes  necessary  to  select  a  paper  that 
is  very  strong,  well  sized,  and  as  little  porous  as  possible.     By  means  of  a  large  brush  or 
sponge  apply  the  sensitizing  liquid  very  equally  in  very  thin  and  smooth  coats ;  then 
dry  as  rapidly  as  possible  with  heat  without  exceeding,  however,  a  temperature  of  55°  C. 
(131°  F.).     The  paper  should  dry  in  obscurity,  and  be  kept  away  from  light  and  damp- 
ness; notwithstanding  all  these  precautions,  it  does  not  keep  well  long,  and  if  it  is 
desired  to  act  with  some  certainty  it  is  better  to  have  a  stock  to  last  only  a  fortnight. 
Freshly  prepared  it  is  better  than  a  few  days  afterward.     It  should  be  of  a  yellow  color. 

C.  Printing :  The  tracing,  made  with  very  black  ink,  is  placed  in  the  printing-frame, 
the  drawing  in  direct  contact  with  the  plate;  then  place  over  it  the  sensitized  paper,  the 
prepared  side  in  contact  with  the  back  of  the  tracing.     There  is  no  necessity  to  make 
use  of  photometric  bands  as  the  progress  of  insulation  is  sufficiently  seen  on  the  sensitized 
paper  during  the  exposure.     From  yellow  that  it  was  it  should  become  perfectly  white 
in  the  clear  portions,  that  is  to  say,  upon  which  there  is  no  drawing  of  the  transfer  or 
positive  cliche  that  is  to  be  copied;  this  is  ascertained  by  raising  from  time  to  time  the 
shutter  of  the  frame.     The  exposure  lasts  from  ten  to  twelve  minutes  in  the  sun ;  in 


496         WILSON'S  QUARTER  CENTURY  IN   PHOTOGRAPHY. 

or  any  other  suitable  compounds  of  tannin  or  such  other  agents  as  are  known 
and  employed  to  produce  color  reactions  with  salts  of  iron.  Mr.  Powell  pre- 
pared his  coloring  bath  of  four  grains  of  gallic  acid  to  the  ounce  of  water,  in 
which  immerse  the  print  and  then  watch  carefully  for  the  development  of  the 
desired  color,  which,  when  it  appears,  is  the  signal  to  remove  the  print  from 
the  coloring  bath  and  to  pass  it  once  rapidly  through  one  bath  of  clean  water 
so  as  to  wash  it  fairly,  then  immediately  blot  off  all  superfluous  water  and  dry 
it  in  full  daylight,  and  preferably  in  the  sun,  which  strengthens  and  increases 
its  brilliancy.  There  can  be  no  doubt  that  by  the  above  process  brilliant  pic- 
tures, with  varied  and  agreeable  tints  and  tones,  can  be  produced ;  sharp,  and 
at  the  same  time  pleasantly  graded.  By  the  old  process  with  the  alcoholic 
solution  of  caustic  potash,  there  was  almost  always  a  blurring  effect  produced, 
which  no  doubt  caused  it  to  fall  in  disuse.  The  time  elapsing  between  the 
printing  and  drying  of  these  prints,  together  with  the  ease  of  manipulation, 
variety  of  tones,  and  I  think  durability,  would  seem  to  recommend  this 
process. 

summer  less,  in  winter  more.  When  the  exposure  is  ended  remove  the  print  from  the 
frame,  and  it  should  show  a  yellow  drawing  upon  a  white  ground.  If  in  the  sensitizing 
bath  a  few  cubic  centimetres  of  a  rather  highly  concentrated  solution  of  sulphocyanide 
of  potassium  have  been  added,  this  bath  becomes  blood-red  and  colors  the  paper  the 
same ;  in  this  case  the  print  also  whitens  during  exposure,  but  then  the  image  instead  of 
being  yellow  is  red  on  a  white  ground.  This  substance,  however,  is,  if  we  may  so  speak, 
inert,  or  without  any  other  action ;  it  is  very  fugitive  and  even  disappears  in  a  short 
time  in  obscurity  ;  it  has  no  other  use,  therefore,  than  to  render  the  drawing  or  the  image 
more  visible  after  exposure. 

D.  Developing  the  prints :  When  the  print  has  been  sufficiently  exposed  it  is  taken 
from  the  pressure-frame  and  floated  for  a  minute  in  the  following  solution,  so  that  the 
side  upon  which  is  the  image  should  alone  be  in  contact  with  the  surface  of  the  liquid, 
avoiding  air-bubbles  between  the  two  surfaces.  Otherwise  defects  would  be  found  in  the 
print;  to  ascertain  this,  raise  in  succession  the  four  corners.  The  developing  bath  is 
composed  as  follows :  Gallic  acid  (or  tannin),  31-46  grains  ;  oxalic  acid,  1^  grains ;  water, 
34  ounces. 

In  this  bath  the  orange-yellow  or  red  lines  are  changed  into  gallate  or  tannate  of  iron, 
and  form,  consequently,  a  veritable  black  writing  ink,  and  as  permanent  as  it.  The  print 
is  then  plunged  into  ordinary  water,  well  rinsed,  dried,  and  the  print  is  now  finished. 
The  violet-black  lines  become  darker  in  drying,  but  unfortunately  the  ground  which 
appears  of  a  pure  white  often  acquires,  in  drying,  a  light  violet  tint.  For  prints  with 
half  tones  this  is  of  no  importance ;  but  for  the  reproduction  of  plans,  for  example,  it  is 
very  objectionable.  By  this  process  we  have  the  satisfaction  of  obtaining  a  drawing  in 
black  lines  similar  to  the  original,  and  in  most  cases  this  is  sufficient. — A.  FISCH. 


PECULIAR    PRINTING    PROCESSES.  497 

218.  PHOTOGRAPHS  ON  PORCELAIN  GLASS. — History  repeats  itself  in 
photography  as  well  as  in  other  departments  of  the  world's  work.  There  are 
indications  of  a  revival  in  the  always  beautiful  photographs  on  porcelain  glass. 
The  old  collodion  method  was  productive  of  lovely  results,  but  the  difficulty  of 
washing  them  properly  rendered  them  liable  to  be  fugitive.  For  this  reason 
they  grew  unpopular. 

218.  The  glass  should  first  be  albumenized,  and  then  coated  with  collodio-chloride  and 
dried. 

Formulas. — Collodion  :  Alcohol,  8  ounces ;  ether,  8  ounces ;  iodide  of  ammonium,  40 
grains;  iodide  of  cadmium,  40  grains;  bromide  of  potassium,  32  grains;  soluble  cotton, 
80  grains. 

More  or  less,  as  the  case  may  require,  to  give  the  collodion  the  proper  flowing  con- 
sistency. 

Dissolve  the  iodides  in  the  alcohol  and  ether ;  then  dissolve  the  bromide  of  potassium 
in  a  minimum  quantity  of  water,  and  add  it  to  the  alcohol  and  ether ;  filter  out  the 
precipitate,  and  then  add  the  cotton  and  enough  tincture  of  iodine  to  give  the  collodion 
a  positive  wine  color. 

Silver  bath :  Water,  64  ounces ;  nitrate  of  silver,  7£  ounces. 

Dissolve  the  silver  in  two-thirds  of  the  water,  and  add  a  solution  of  iodide  of  potas- 
sium, dissolved  in  water,  enough  to  give  a  precipitate  which  will  not  dissolve  in  about 
five  minutes.  Then  add  the  other  kind  of  the  water,  and  filter  perfectly  clear.  Acidulate 
with  two  drachms  of  pure  glacial  acetic  acid.  Then  try  the  bath,  as  it  should  give  clear, 
brilliant  effects  on  ordinary  glass,  by  the  camera. 

Salt  solution :  Water,  1  quart ;  salt,  160  grains. 

Preservative  solution  :  Water,  8  ounces ;  gallic  acid,  8  grains ;  citric  acid,  8  grains. 

This  solution  and  No.  1  of  the  developing  solution  should  be  mixed  fresh  every  time 
they  are  to  be  used,  as  they  will  lose  their  properties  by  standing  about  a  day. 

Developing  solutions:  No.  1.  Water,  4  ounces;  pyrogallic  acid,  6  grains;  citric  acid, 
6  grains.  No.  2.  Water,  1  ounce ;  nitrate  of  silver,  20  grains ;  citric  acid,  40  grains. 
This  solution  may  be  kept  and  used  until  the  precipitate  begins  to  fall,  when  it  is  better 
to  mix  more  fresh  solution. 

Toning  bath :  Dissolve  45  grains  hyposulphite  of  soda  in  32  ounces  of  water ;  then 
dissolve  15  grains  chloride  of  gold  in  16  ounces  of  water,  and  add  it,  little  by  little,  to  the 
hyposulphite  solution.  Shake  well,  and  when  the  mixture  becomes  clear  as  water,  it  is 
then  fit  for  toning.  Pour  about  an  ounce  of  this  solution  in  a  small  bottle,  then  apply 
repeatedly,  until  the  desired  tone  is  attained.  After  using,  reject  the  solution,  as  it  does 
not  tone  well  a  second  time. 

Coloring  solution :  Alcohol,  8  ounces ;  gum  camphor,  2  grains ;  bleached  shellac, 
pulverized,  24  grains. 

Place  the  ingredients  in  a  bottle,  and  set  in  a  warm  place,  shaking  it  occasionally,  for 
about  a  day.  Filter  through  paper,  and  it  is  ready  for  use.  It  is  necessary  to  state  that 
all  the  solutions  should  be  filtered  clear,  and  kept  free  from  suspended  particles. 

32 


498         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

219.  The  albumen  process  was  offered  as  a  substitute  for  collodion,  but, 
though  giving  more  assurance  of  permanence  and  equally  fine  results,  it  came 
too  late  and  porcelain  pictures  went  out  of  fashion  so  to  speak.     It  may  be  that 
there  was  a  little  unfairness  about  this,  for  as  late  years  have  proven,  some 
porcelain  pictures  nearly  twenty  years  old,  still  retain  their  color  and  beauty. 

220.  Thanks  to  Mr.  Carbutt  and  others,  newer  and  surer  methods  have  been 
given  us,  wherein  gelatine  offers  a  helping  hand.     Those  who  were  disappointed 

Fixing  solution:  Hyposulphite  of  soda,  1  pound;  water,  24  ounces. 

In  order  to  obtain  sharp  pictures  on  uneven  glass,  I  use  an  extension  box  or  tube 
placed  in  front  of  the  printing-frame,  the  length  of  which  should  be  about  three  feet  and 
tapering  toward  the  end,  so  as  to  admit  of  an  aperture  large  enough  to  receive  a  quarter- 
plate  tube.  By  placing  the  tube  toward  the  heavens,  and  receiving  the  light  from  it  on 
the  negative,  a  sharp  picture  can  be  made  on  glass  which  would  otherwise  be  useless. — 
H.  M.  JOHNSTON. 

219.  For  the  collodio-albumen  process,  proceed  by  making  up  the  following :  Silver 
nitrate,  1200  grains ;  water,  4  ounces. 

Dissolve  the  silver  in  the  water,  take  out  one-third,  and  set  aside ;  add  concentrated 
ammonia  to  the  remaining  two-thirds,  which  will,  of  course,  turn  chocolate  color ;  keep 
on  adding  until  clear;  now  add  the  one- third  to  the  two-thirds.  Now  add  nitric  acid 
until  almost  acid,  but  still  neutral.  It  will  be  observed  that  you  commenced  with  a 
little  better  than  four-ounce  silver  solution ;  by  pouring  intd  the  graduate,  you  will  find 
that  it  has  doubled  itself,  that  is,  you  have  a  prepared  silver  solution  of  eight  ounces ; 
this  can  be  used  until  it  is  entirely  used  up.  Filter,  and  it  is  ready  for  use.  In  printing, 
it  should  print  a  rich  sepia,  but  should  only  be  printed  a  shade  deeper  than  the  regular 
paper  print. 

Tone  in  the  toning  bath  used  for  albumen  prints,  but  carry  the  tone  a  little  further 
than  you  would  prints  that  have  been  salted  previous  to  toning.  The  porcelain  print  is 
merely  washed  under  the  tap  a  few  minutes,  and  then  placed  in  the  toning-dish  and 
toned.  Soda  them  in  the  same  soda  as  used  for  paper  prints,  letting  them  remain  for 
five  to  eight  minutes.  Wash  in  running  water  same  length  of  time  as  paper  prints.  I 
usually  wash  both  porcelains  and  paper  prints  about  three  hours,  and  let  them  dry 
spontaneously. — GEORGE  W.  SCHELL. 

220.  The  development  of  chloride  films  on  opal  plates  is  similar  to  the  development  of 
the  chloride  paper,  which  refer  to  on  page  478. 

The  sensitive  film  is  exposed  in  contact  with  the  negative  to  diffused  or  artificial 
light.  The  image  should  show  gradually ;  if  it  flash  out,  either  the  exposure  is  too  much 
or  the  developer  needs  a  little  bromide ;  one  to  three  drops  of  a  fifty  grain  solution  of 
bromide  to  each  ounce  of  developer  has  a  strong  restraining  action  in  the  presence  of  the 
citric  acid  and  chloride  of  ammonium ;  for  very  warm  tones,  dilute  developer  with  equal 
parts  of  water  and  add  one  or  two  drops  of  bromide  solution  to  each  ounce  of  developer, 
but  be  sure  and  give  at  least  double  the  exposure ;  do  not  carry  the  development  of  the 
opals  too  far,  as  they  lose  very  little  in  fixing.  For  a  positive  picture  on  opal,  the 


PECULIAR    PRINTING    PROCESSES.  499 

by  the  destruction  of  their  old  efforts  may  come  back  now,  assured  that  the 
danger  is  over. 

221.  Porcelain  pictures  may  be  made  by  contact  printing  as  in  the  copying 
camera.  By  the  latter  method  old  or  any  size  of  negatives  may  be  utilized. 

development  should  be  arrested  the  moment  the  detail  shows  in  the  high  lights,  and  this 
is  most  effectually  done  by  quickly  removing  the  plate  from  the  developer,  and  flushing 
over  the  surface  a  five  grain  solution  of  potassium  bromide  ;  this  instantly  arrests  de- 
velopment and  preserves  the  brilliancy  of  the  image. 

Wash  and  fix  in  solution  No.  3,  wash  a  few  minutes  and  immerse  for  one  minute  in 
solution  No.  4 ;  wash  thoroughly,  and  before  placing  to  dry  go  over  the  surface  with  a 
swab  of  absorbent  cotton  while  water  is  flowing  over  it,  then  dry  spontaneously.  Opal 
plates  with  matt  surface  for  artistic  work  are  also  made. 

There  are  few  productions  of  photography  more  pleasing  than  these  opal  plates.  There 
is  a  softness  and  harmony  in  the  gradations  of  tone  and  a  brilliancy  in  the  whole,  which 
make  it  a  pleasure  to  look  at  them. — JOHN  CARBUTT. 

221.  The  negative  to  be  copied  on  the  porcelain  plate  is  fixed  in  the  shield  wrong  side 
up,  and  with  the  film  to  the  lens.  The  negative  which  is  suited  for  such  sort  of  work, 
must  be  very  thin,  transparent,  and  yet  full  of  detail ;  it  must  be  much  thinner  in  the 
opaque  parts  than  an  ordinary  negative  for  paper  prints ;  and  it  is  well  not  even  to  var- 
nish the  negative,  because  a  layer  of  varnish  is  apt  to  detract  from  the  transparency  of 
the  film  or  to  leave  small  particles  of  opaque  matter  on  its  surface. 

Most  generally  the  picture  is  required  to  be  of  the  same  size  as  that  on  the  negative ; 
therefore,  slide  the  camera  under  the  lid  until  the  middle  of  the  lens  is  about  sixteen 
inches  from  the  negative,  and  focus  the  negative  on  the  ground-glass  by  moving  the  bel- 
lows part  of  the  camera.  If  the  picture  on  the  ground-glass  is  now  of  the  same  size  as 
that  on  the  negative,  no  further  adjustment  is  needed ;  but  if  it  is  larger,  then  draw  the 
whole  camera  (not  the  bellows  part)  a  little  back  and  focus  and  measure  again.  If,  on 
the  contrary,  the  picture  on  the  ground-glass  were  larger  than  that  on  the  negative,  you 
must  slide  the  camera  forwards  to  the  front.  As  soon  as  the  exact  position  is  once  found 
where  the  two  pictures  are  of  the  same  size,  the  camera 
is  fixed  or  clamped  in  this  position;  and  a  mark  is 
made  by  means  of  which  the  camera  can  again  be  placed 
in  the  same  position  if  it  should  be  removed  for  other 
purposes.  Top  light  is  best. — A.  N.  ADEPT. 

I  have  devised  an  elastic  frame  specially  adapted  for 
the  printing  of  positives  on  opal  glass  (Fig.  378).  This 
frame,  owing  to  its  construction,  allows  the  following  of 
progress  of  the  impression  without  disturbing  the  nega- 
tive, which  is  kept  in  its  frame  against  the  plate,  by 
means  of  a  spring;  on  the  other  hand,  when  it  is  desir- 
able  not  to  cut  a  negative  on  which  there  are  several 

images,  a  piece  of  sheet-iron,  rather  thinner  than  the  opal  glass,  is  fitted  to  the  frame. 
Of  this  plate  a  corner  is  removed  of  the  size  of  the  positiv.e  print,  which  is  thus  rigidly 


500         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

By  the  former  a  special  printing  frame  is  most  convenient,  though  a  plan  for 
dispensing  with  it  is  added  to  the  notes. 

222.  One  of  the  prettiest  applications  of  the  porcelain  or  opalotype  process 
is  the  making  of  pictures  on  watch-dials.  It  is  a  wonder  that  more  of  it 
is  not  done.  And  now,  tiny  miniatures  on  porcelain  for  pins,  decorations, 
and  so  on,  would  meet  the  fashion,  and  should  become  very  popular. 

For  such  the  polished  glass  would  be  best  for  plain  pictures,  and  the  ground 
surface  for  such  as  are  to  be  colored. 

It  seems  as  though  porcelain  transparencies  should  also  become  much  sought 
after  if  properly  presented  to  lovers  of  the  beautiful. 

held  by  the  spring  shown  in  the  figure.  The  lower  part  of  this  frame  being  elastic,  the 
image  is  always  in  perfect  contact  with  the  nep-ative  by  the  pressure  of  the  spring. 

The  contact  should  be  very  rigid  to  obtain  the  half  tones ;  because,  besides  losing  a 
great  deal  of  its  intensity  in  the  toning  and  fixing  baths,  the  image  seen  by  transparency 
through  the  opaline  medium  never  has  the  same  vigor  as  when  seen  directly  by  reflec- 
tion.—M.  LlEBERT. 

222.  I  do  not  claim  the  idea  of  photographing  on  a  watch-dial,  in  fact  do  not  know  the 
author,  but  send  you  mine.  I  have  put  from  one  to  three  heads  on  one  dial  from  as 
many  different  negatives.  After  taking  off  the  dial,  or  having  it  removed  by  a  watch- 
maker, take  a  square  piece  of  cardboard,  half  an  inch  larger  than  the  dial,  place  the  dial 
centrally  on  it,  and  press  very  lightly,  just  sufficient  to  make  an  impression  of  the  pins 
that  hold  the  dial  to  the  watch.  With  a  large  pin,  or  other  metal  point,  pierce  through 
the  card  at  the  spots  marked,  place  the  dial  on  the  card,  gently  pressing  the  pins  through 
the  holes.  Now  supposing  you  wish  to  put  one  portrait  on,  place  a  straight  edge  of  card- 
board over  the  dial  so  as  to  bisect  the  XII  and  VI,  make  a  mark  on  the  cardboard  from 
the  dial  to  the  edge.  Should  there  be  lettering  immediately  under  the  XII,  then  draw 
the  line  to  one  side  of  the  centre.  Now  place  the  straight  edge  across  the  dial  so  as  to  cut 
about  nine  minutes  on  each  side  of  the  XII,  and  mark  to  the  edge  of  the  card ;  take  up 
the  dial  and  card,  make  short  marks  on  the  back  to  correspond  with  those  on  the  front. 
These  are  to  be  the  guides  to  aid  you  in  placing  the  dial  in  its  proper  place  on  the  nega- 
tive. Remove  the  dial  from  the  card,  clean  the  face  with  chamois  leather  to  free  from 
dust,  etc.,  flow  over  it  a  mixture  of  albumen  and  water  in  equal  proportions.  Coax  oft' 
any  surplus  that  hangs  to  the  edge  with  blotting-paper.  When  dry,  replace  on  the 
cardboard,  and  flow  with  collodio-chloride  of  silver ;  set  aside  in  the  dark  to  dry.  While 
thus  drying,  prepare  the  negative  by  drawing  a  line  with  a  pencil  on  each  side,  and  in  a 
line  with  the  top  of  the  head,  also  a  line  above  and  below  the  head,  that  would  bisect 
the  figure,  if  drawn  through.  Make  a  small  vignette  mask  out  of  strawboard,  one-eighth 
of  an  inch  thick,  and  sufficiently  large  in  surface  to  shield  the  dial  from  all  action  of 
light,  except  what  passes  through  the  vignette  opening ;  fasten  to  the  back  of  the  nega- 
tive with  gum  paper ;  secure  the  negative  in  the  printing-frame.  The  dial  being  now 
ready  place  it  face  down  on  the  negative,  observing  that  the  lines  on  the  back  of  the  card 


PECULIAR'  PRINTING    PROCESSES.  501 

223.  CARBON  PRINTING. — Several  futile  efforts  have  been  made  to  substitute 
carbon  or  pigment  printing  for  the  albumen  paper  process.  The  manipulations 
are  so  entirely  different  as  to  make  them  distasteful  to  the  conservative  photog- 
rapher ;  and  the  results,  though  charming  and  doubtless  permanent  did  not 
take  with  the  public.  So,  like  an  unpopular  comedian,  carbon  had  to  step 
down  and  off  the  stage  of  popularity. 

exactly  correspond  with  those  on  the  negative.  On  the  card  and  between  the  pins  lay  a 
piece  of  the  straw-boa^d,  thick  enough  to  protect  the  pins  of  the  dial  from  receiving  any 
pressure.  If  not  so  protected,  the  dial  might  be  injured.  Place  a  piece  of  cotton  velvet 
over  the  whole,  taking  care  not  to  change  the  position  of  the  dial.  An  ordinary  stereo- 
scopic plate  and  printing-frame  can  be  used,  taking  the  negative  on  one  end  of  the  plate. 
Block  up  one  end  of  the  printing-frame  to  the  thickness  of  the  dial  and  cardboard  ;  let 
the  pressure  of  the  springs  be  light;  by  holding  the  frame  in  such  a  position  as  to  lift 
the  negative  off  from  the  dial,  the  progress  of  the  printing  can  be  examined  with  very 
little  danger  of  moving  the  impression.  When  printed,  wash,  tone,  and  fix,  as  recom- 
mendegl  for  other  collodio-chloride  prints.  Dry  and  replace  on  the  watch.  I  use  no 
varnish,  as  I  think  it  best  not  to  do  so. — J.  CARBUTT. 

223.  Carbon  tissue  is  the  material  upon  which  the  prints  are  made.  A  mixture,  in 
proper  proportions,  of  gelatine,  water,  sugar,  and  India-ink,  or  other  pigments,  is  applied 
warm  to  paper,  and  adhesion  thereto  secured  by  pressure. 

To  prepare  and  sensitize  the  tissue  lay  the  sheet  to  be  sensitized  on  any  hard,  smooth 
substance,  and  rub  or  wipe  the  printing  surface  gently  with  a  clean  soft  linen  cloth  or 
piece  of  cotton-flannel.  Avoid  touching  the  tissue  with  the  hands  or  fingers.  After 
rubbing,  take  it  by  two  corners,  immerse  it  in  the  sensitizing  solution,  and  drawing  it 
through  the  same,  dexterously  turn  it  over  and  allow  it  to  remain,  face  down,  three  or  four 
minutes.  The  sensitizing  solution  is  made  as  follows:  Bichromate  of  potash,  1  ounce; 
cold  water,  30  ounces. 

This  solution  will  keep  in  stock  any  length  of  time,  and  it  is  wise  to  make  more  at  a 
time  than  is  actually  needed. 

Lighting  the  Tissue. — When  about  to  print,  place  the  tissue  in  the  printing-frame  as 
usual  with  other  papers.  It  appears  a  little  singular  to  place  black  instead  of  white 
paper  in  the  frame  and  expose  it  to  light. 

The  time  of  exposure  must  be  judged  of  by  the  skilful  printer. 

After  lighting,  the  tissue  is  fastened  by  the  corners  on  a  glass  plate,  with  the  printing 
surface  uppermost,  by  means  of  clothes-clips.  Then,  with  a  soft  camePs-hair  brush,  var- 
nish the  printing  surface  with  an  even  coating  of  the  "  hydrocarbon  varnish,"  and  lay 
away  to  dry.  Take  a  piece  of  Saxe  paper,  which  has  been  previously  floated  till  saturated 
on  the  hydrocarbon  varnish,  and  very  thoroughly  dried,  and  place  the  varnished  side  of 
it  on  the  varnished  surface  of  the  tissue,  and  gently  press  them  together  with  the  hand. 

When  dry  remove  and  lay  the  two  adhering  sheets  on  a  piece  of  smooth  cardboard, 
with  the  Saxe  paper  uppermost,  cover  them  with  a  piece  of  felt  cloth,  the  Saxe  paper 
being  next  to  the  felt  cloth;  then  place  another  piece  of  cardboard  on  the  felt  cloth,  and 


502         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

It  is  yet  used  in  Europe  very  largely  for  enlargements,  reproductions,  and 

fac-similes,  though  bromo-gelatine  has  recently  had  a  pick  at  its  usefulness  too. 

For  these  reasons  only  a  few  descriptive  notes  are  added  concerning  two  or 

pass  the  whole  through  a  press.  The  pressure  must  not  be  too  heavy  nor  too  light,  but 
about  equal  to  the  weight  of  a  roll  weighing  about  eight  hundred  pounds.  This  will  be 
found  quite  sufficient  for  4  x  4  prints,  and  all  smaller,  and  the  same  proportion  of  pres- 
sure for  larger  sizes. 

After  coining  from  the  rolls,  the  print  must  be  handled  carefully,  and  placed,  with  the 
Saxe  paper  uppermost,  in  a  water-bath,  heated  from  95°  to  100°  Fahrenheit.  When  it 
is  found  that  the  corners  will  slip  or  slide  apart,  commence  to  pull,  very  delicately,  on 
the  two  papers,  keeping  them  all  the  time  below  the  surface  of  the  water.  As  soon  as 
they  are  separated,  throw  out  the  paper  which  first  held  the  tissue.  Continue  to  wash 
the  prints  in  this  water  heated  from  95°  to  100°  F.,  until  all  the  unaltered  gelatine  and 
bichromate  are  dissolved,  and  until  the  print  is  fully  out. 

As  soon  as  the  print  is  thoroughly  developed,  it  must  be  placed  in  a  vessel  of  clean 
cold  water,  which  must  be  very  frequently  changed,  or  placed  under  a  tap,  and  allowed 
to  remain  there  for  two  or  three  hours  or  more,  then  removed  and  hung  up  by  clips 
to  dry. 

When  dry,  the  picture  is  to  be  nicely  and  evenly  coated  with  a  solution  made  of — 
Cox's  sparkling  gelatine,  1  ounce;  cold  water,  8  ounces;  glycerine  (pure),  80  drops; 
white  sugar,  J  ounce. 

This  should  be  made  in  quantities  as  wanted ;  fresh  every  time,  in  order  to  insure  a 
good,  sweet  strong  glue.  It  ferments  very  quickly,  which  reduces  its  strength. 

Warm  slowly,  just  enough  to  melt  the  gelatine,  and  use  warm.  When  a  number  of 
prints  are  to  be  done,  it  is  well  to  tack  them  by  the  four  corners  to  a  board,  and  let  them 
be  coated  and  dried  on  it. 

As  soon  as  the  coating  of  glue  is  dry,  the  print  is  to  be  laid,  face  down,  on  a  piece  of 
wet  or  moist  paper,  on  which  it  is  to  remain  permanently,  and  passed  between  rollers, 
with  the  felt-cloth  and  cardboard,  as  before  described;  but  this  time  with  a  heavy 
pressure 

When  dry,  take  a  very  fine  sponge — or  a  wad  of  cloth,  made  like  a  copper-plate 
engraver's  "  rubber  " — and  moisten  it,  not  saturate  it,  with  some  of  the  liquid  from  the 
bottle  labelled  "  Transferring  Solution." 

If  .the  "transferring  solution"  is  well  applied,  the  Saxe  paper  will,  from  the  peculiar 
action  of  the  solution,  in  combination  with  the  peculiar  nature  of  the  varnish,  frequently 
roll  off  itself  from  the  picture. 

After  the  Saxe  paper  is  removed  and  the  print  becomes  dry,  it  must  be  immersed  for 
about  five  minutes  in  a  solution  of  alum  and  water,  made  by  dissolving  one  ounce  of 
alum  in  thirty-two  ounces  of  water.  Immersing  the  print  in  alum  is  called  tanning  it,  as 
the  action  of  the  alum  makes  leather  of  the  picture.  After  tanning,  wash  or  rinse,  under 
the  tap?  for  four  or  five  minutes.  This  completes  the  operation,  and  the  picture  may 
now  be  mounted  with  starch,  or  any  other  adhesive  material,  in  the  usual  mode  of 
mounting  silver  prints. — EDWARD  L.  WILSON. 


PECULIAR    PRINTING    PROCESSES. 


503 


three  of  the  numerous  so-called  carbon  processes,  generally  classed  as  "double 
transfer,"  "  single  transfer,"  and  "  direct." 

Those  who  need  further  details  for  practice  can  find  them  in  full  in  the 
magazines  and  manuals  specially  devoted  to  carbon  printing. 

The  manipulations  for  producing  Argento  pictures  are  briefly  as  follows  : 

A  carbon  print  is  made  by  exposing  a  piece  of  carbon  tissue,  sensitized  by  bichromate 
of  potash,  under  an  ordinary  negative  in  the  usual  way  of  printing  carbon  prints.  The 
difficulty  heretofore  in  making  carbon  prints  has  been  on  account  of  bad  carbon  tissue. 
I  therefore  prepare  the  tissue  for  this  process  according  to  my  own  method. 

After  the  carbon  print  is  printed,  a  metal  plate  with  a  silvered  surface  is  taken  and 
ribbed  by  rubbing  it  with  a  sanded  brush,  to  deaden  the  polish  and  to  give  effect  to  the 
picture. 

The  plate  is  then  cleansed  with  spittle  (rather  paradoxical,  but  nothing  else  answers 
the  purpose  as  well),  and  then  laid  upon  a  sheet  of  paper  on  a  table  and  flowed  with 
diluted  alcohol.  The  carbon  print  is  now  laid  face  down  upon  the  plate,  paper  laid  upon 
it,  and  a  squeegee  (of  the  form  shown  in  Fig.  379  and  made  of  a  piece  of  wood  and 
several  thicknesses  of  ordinary  bed-ticking  wrapped  over  one  end ;  see  cut),  used  to  force 
out  the  superfluous  alcohol  between  the  picture  and  the  plate,  and  to  make  the  one  adhere 
to  the  other.  The  alcohol  also  serves  to  prevent  the  occurrence  of  air-bubbles. 

The  whole  is  now  immersed  in  a  pan  of  water  of  about  90°  temperature.  In  a  very 
few  moments  the  paper  may  be  detached  from  the  gelatine,  and  the  parts  of  the  latter 
unaffected  by  light  will  shortly  be  dissolved,  leaving  on  the  plate  a  picture  the  shades  of 


FIG.  379. 


FIG.  380. 


which  consist  of  the  colored  gelatine,  and  the  lights,  or  rather  the  highest  lights,  of  the 
surface  of  the  plate  exposed  under  colorless  gelatine.  This  part  of  the  operation  is  most 
fascinating  and  beautiful — more  like  the  developing  of  a  collodion  plate  than  anything 
else. 

As  soon  as  the  superfluous  color  is  all  washed  away,  the  pictures  (now  on  the  metal 
plates)  are  removed  from  the  water,  and  hung  upon  a  line  by  clips  to  dry. — F.  A. 
WENDEROTH. 


dHAPTEK   XXII. 

COLOR-SENSITIVE   PHOTOGRAPHY — ISOCHROMATIC  ;    ORTIIOCHROMATIC. 

224.  To  secure  the  proper  color  tone  of  nature  in  a  resulting  photograph 
has  been  the  effort  of  many  an  industrious  worker  for  many  years.  To  give  a 
history  of  all  such  experiments  would  require  more  space  than  can  be  afforded 
here. 

Be  it  known  that,  thanks  to  Vogel,  Ives,  Mailman,  Scolik,  and  a  few 
others,  bromo-gelatine  plates  are  supplied  which  will  secure  color-value  and 
which  are  almost  as  sensitive  as  ordinary  plates.  Thus  a  light-looking  color 
results  light  in  the  positive  print,  and  vice  versa. 

For  landscapes,  copies  of  paintings,  interiors  of  dwellings ;  for  portraiture 
where  the  costumes  are  colored,  and  in  many  ways  the  color-tone  plate  will  be 
found  a  great  help. 

224.  My  method  consists  in  treating  ordinary  collodio-bromide  emulsion  plates  with 
blue-myrtle  chlorophyl  solution,  exposing  them  through  the  yellow  screen,  and  then 
developing  them  in  the  usual  manner.  The  emulsion  which  I  have  employed  is  made 
with  an  excess  of  nitrate  of  silver,  which  is  afterward  neutralized  by  the  addition  of 
chloride  of  cobalt;  it  is  known  as  Newton's  emulsion.  I  now  prepare  the  chlorophyl 
from  fresh  blue-myrtle  leaves,  by  cutting  them  up  fine,  covering  with  pure  alcohol,  and 
heating  moderately  hot ;  the  leaves  are  left  in  the  solution,  and  some  zinc  powder  is 
added,  which  helps  to  keep  the  chlorophyl  from  spoiling.  A  glass  plate  is  flowed  with 
the  emulsion,  and  as  soon  as  it  has  set  the  chlorophyl  solution  is  applied  for  a  few 
seconds,  after  which  the  plate  is  washed  in  pure  water  until  smooth,  when  it  is  ready  for 
exposure. 

My  color-screen  consists  of  a  small  plate-glass  tank,  having  a  space  of  three-sixteenths 
of  an  inch  between  the  glass,  filled  with  a  solution  of  bichromate  of  potash  about  one 
grain  strong.  I  place  the  tank  in  front  of  the  lens,  in  contact  with  the  lens-mount.  The 
advantage  of  this  tank  and  solution  is  that  it  can  be  more  easily  obtained  than  yellow 
plate  glass,  and  the  color  can  be  adjusted  to  meet  any  requirement. 

The  plates  require  about  three  times  as  much  exposure  through  the  yellow  screen  as 
without  it,  and  may  be  developed  with  the  ordinary  alkaline  pyro  developer. 

In  order  to  illustrate  the  value  of  this  process,  I  made  two  photographs  of  a  highly 

colored  chromo-lithograph,  representing  a  lady  with  a  bright  scarlet  hat  and  purple 

feather,  a  yellow-brown  cape,  and  a  dark-blue  dress.     One  by  the  ordinary  process, 

represents  the  blue  as  lighter  than  the  yellow-brown,  the  bright  scarlet  hat  as  black,  and 

(504) 


COLOR-SENSITIVE    PHOTOGRAPHY. 


505 


225.  To  accomplish  this  the  ingenious  discoverers  immerse  their  plates  in  a 
bath,  or  else  expose  them  with  a  peculiarly  stained  glass  placed  between  the 
lens  and  plate.  I  have  selected  from  the  best  instructors  we  so  far  have  in  the 

the  purple  feather  as  nearly  white.     The  other,  by  the  chlorophyl  process,  reproduces 
all  colors  in  nearly  the  true  proportion  of  their  brightness,  but  with  a  slight  exaggeration 


FIG.  381. 


FIG.  382. 


From  or  Unary  photogn.pb  of  chromo-lithograph. 


From  isochromatic  photograph. 


of  contrast  produced  purposely  by  using  a  too  strong  color  solution  in  the  small  tank. 
These  photographs  are  herewith  reproduced  (see  Figs.  381  and  382). — F.  E.  IVES. 

225.  My  invention  relates  to  an  improved  process  for  manufacturing  color-sensitive 
isochromatic  or  orthochromatic  photographic  emulsions  or  plates  by  dyeing  the  same 
with  dyes  highly  sensitive  to  light.  In  the  year  1873, 1  discovered  that  the  sensitiveness 
of  the  haloid  salts  of  silver  for  green,  yellow,  and  red  rays  of  light,  which  is  very  feeble, 
can  be  augmented  by  the  addition  of  bodies  which  absorb  such  rays. 

I  discovered  that  all  the  red,  violet,  and  blue  chinoline  and  pyrodine  dyes,  which 
cannot  be  employed  by  dyers,  on  account  of  their  fading  so  rapidly  when  exposed  to 
light,  are  first-class  optical  sensitizers  for  photographic  plates. 


506         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

early  youth  of  this  promising  discovery,  such  Dotes  as  will  make  the  matter 
plain  before  my  readers  and  keep  history  up  to  the  date  of  publication. 

The  application  of  the  aforementioned  dyes  is  extremely  easy;  for  instance  (a),  the 
dye  is  either  dissolved  in  alcohol  in  the  proportion  of  about  1 :  1000  alone  or  mixed  with 
other  colors,  and  then  mixed  with  the  prepared  emulsion,  and  with  or  without  an  addi- 
tion of  liquor  of  ammonia  or  carbonate  of  ammonia;  or  (#),  the  dye  is  dissolved  in  water 
alone,  or  mixed  with  other  dyes,  with  or  without  adding  liquor  of  ammonia  or  carbonate 
of  ammonia  to  the  solution.  The  quantity  of  dye  to  be  added  to  the  emulsion  varies 
according  to  the  quality  of  the  latter,  and  must  be  determined  by  an  experiment.  An 
excellent  formula  for  many  emulsions  is:  2  to  4  cubic  centimetres  of  a  solution  of 
chinoline  red  in  alcohol  (1  to  500),  5  drops  of  a  solution  of  cyanine  (1  to  500),  100  cubic 
centimetres  of  water,  1  cubic  centimetre  of  liquor  of  ammonia.  The  emulsion^lates  are 
dipped  or  steeped  in  this  solution  for  one  minute,  and  then  dried. — DR.  H.  W.  VOGEL. 

After  trying  various  proportions,  I  find  the  following  to  work  fairly  well:  Silver 
nitrate,  20  grains ;  ammonia  carbonate,  90  grains ;  water,  distilled,  16  ounces ;  erythrosin 
(2:100),  10  drachms. 

The  plates  are  placed  in  this  for  two  minutes.  A  rinse  in  distilled  water  gives  less 
chance  of  stains,  and  then  place  in  a  rack  to  dry.  Let  me  here  state  that  if  they  are 
used  in  the  moist  condition  the  orthochromatic  effect  is  practically  nil;  they  must  be 
used  quite  dry.  By  this  treatment  the  plate  is  rendered  three  times  more  sensitive. 

I  must  insist  on  the  necessity  of  using  only  ruby  light,  the  plates  having  now  become 
so  sensitive  to  yellow  that  the  greatest  precaution  must  be  taken  in  handling  them. 

Fog  is  got  rid  of  by  soaking  the  exposed  plate  before  developing  in  the  following : 
Potassium  bromide,  120  grains ;  ammonia,  o  ounce ;  water,  12  ounces. 

Do  not  allow  to  remain  more  than  thirty  seconds,  well  rinse  under  the  tap,  and 
proceed  to  develop  with  any  of  the  usual  developers — ammonia,  potash,  or  ferrous 
oxalate. 

If  there  be  much  blue  in  the  object  to  be  copied,  a  yellow  screen  must  be  used  if 
exposure  is  to  be  made  by  daylight,  although  by  gas  or  lamplight  it  is  quite  unnecessary. 
The  best  effect  is  always  secured  by  gaslight  exposure. 

A  very  good  substitute  for  colored  glass  is  to  color  a  collodion  film  and  strip  it  up  from 
glass.  The  glass  should  be  rubbed  over  with  talc  or  a  solution  of  wax  in  ether,  and  well 
polished  off,  and  coated  with  collodion  containing  methyl  orange.  The  dried  film  should 
appear  decidedly  orange.  The  stripped  film  can  then  be  gummed  to  the  cap  of  lens, 
having  cut  out  the  centre  first,  and  used  preferably  behind  the  lens. 

The  carbonate  of  silver  and  erythrosin  may  be  mixed  with  .an  emulsion,  but  requires 
great  care.  It  should  be  mixed  at  as  low  a  temperature  as  possible,  and  the  plates  used 
as  soon  as  they  are  dry,  as  their  life  is  very  short.  The  orthochromatic  effect  is  very 
marked,  and  the  speed  increased  about  ten  times.  If  anyone  is  desirous  of  trying  this,  I 
give  the  following:  Emulsion  (containing,  say,  200  grains  of  silver),  10  ounces;  silver 
nitrate,  10  grains ;  ammonium  carbonate,  45  grains ;  erythrosin  (2  : 1000),  5  drachms. 

Before  development  they  must  be  treated  with  the  ammonia  and  bromide. — J.  B.  B. 
WELLINGTON. 


COLOR-SENSITIVE    PHOTOGRAPHY.  507 

226.  I  have  DO  doubt  that  some  of  the  drawbacks  which  now  attend  the 
working  of  color-sensitive  plates  will  be  entirely  overcome  ere  long. 

226.  Eder's  Formula. — The  plates  receive  no  preliminary  treatment,  but  are  soaked  for 
two  minutes  in  erythrosin  solution  (1 :500),.2  to  4  parts;  ammonia,  1  part;  water,  200 
parts,  and  dried.  Exposed  plates  are  developed  in  the  ordinary  way,  but  with  a  some- 
what larger  proportion  of  restrainer. 

Spitaler's  Formula  for  Stellar  Photography. — Bathe  the  plates  for  five  minutes  in  eryth- 
rosiri  solution  (1 : 400),  4  parts;  ammonia,  1  part;  distilled  water,  200  parts,  and  allow 
to  dry. 

Loescher's  Formulae. — No  preliminary  bath  is  used,  but  the  plates  are  soaked  for  one 
minute  in  either  of  the  following  solutions  : 

No.  1.  Erythrosin,  alcoholic  solution  (1:1000),  10  parts;  ammonia,  1  part;  water, 
90  parts. 

No.  2.  Saturated  azalin  solution,  4  parts ;  ammonia,  1  part ;  alcohol,  20  parts ;  water 
75  parts. 

If  sensitiveness  to  red  is  required,  No.  2  solution  must  be  used. 

Hasselberg's  Formulce  for  Spectrum  Photography. — The  plates  are  steeped  for  about  one 
minute  in  a  weak  solution  of  ammonia,  and  are  then  immersed  for  two  or  three  minutes 
in  one  of  the  following  solutions  : 

No.  1.  From  C  to  wave-length  5600.  Cyanin,  alcoholic  solution  (1 : 400),  2  parts ;  am- 
monia, 1  part;  distilled  water,  100  parts. 

No.  2.  From  wave-length  5600  to  F.  Chrysaniline  solution  (1 : 1000),  3  parts  ;  eosin 
solution  (1 : 1000),  5  parts;  ammonia,  1  part;  distilled  water,  100  parts. 

Ives's  Process  with  Collodio-bromide  Plates. — This  process  consists  in  the  application  of 
chlorophyl,  or  chlorophyl  and  eosin,  to  a  plate  coated  with  collodio-bromide  emulsion. 
Up  to  the  present  time  chlorophyl  has  not  been  used  successfully  in  conjunction  with 
gelatino-bromide  plates,  but  some  recent  experiments  by  Dr.  Maddox  indicate  that 
chlorophyl  from  the  leaves  of  the  tomato  or  beet  may  give  useful  results,  and  the  ques- 
tion is  worthy  of  careful  investigation.  The  chlorophyl  solution  must  be  fresh  and 
strong.  That  from  the  American  blue  myrtle  or  English  periwinkle  (  Vinca  minor]  gives 
the  best  results,  but  that  from  the  leaves  of  the  plantain  answers  almost  equally  well  and 
gives  slightly  greater  relative  sensitiveness  to  red.  The  fresh  leaves  are  cut  up  into  small 
pieces,  washed  repeatedly  with  warm  water,  then  heated  with  five  times  their  weight  of 
pure  alcohol  for  about  fifteen  minutes,  and  the  solution  filtered  and  allowed  to  cool,  when 
it  is  ready  for  use.  The  solution  will  keep  for  a  few  weeks  in  a  cool  place  in  the  dark, 
but  in  this  case  it  is  advisable  to  leave  the  leaves  in  the  liquid,  and  to  add  a  small  quan- 
tity of  powdered  zinc.  A  plate  is  coated  with  collodio-bromide  emulsion,  allowed  to  set, 
then  covered  with  the  alcoholic  solution  of  chlorophyl  for  a  few  seconds,  and  finally 
washed  with  distilled  water  until  the  surface  is  smooth. 

If  eosin  is  also  to  be  added  the  distilled  water  used  for  washing  is  just  tinted  with  this 
dye.  It  is  important  to  avoid  the  use  of  too  large  a  quantity  of  eosin,  which  would 
diminish  the  sensitiveness  to  yellowish-green. 

Exposed  plates  are  developed  in  a  dim  yellowish-green  light  by  means  of  dry  pyro- 


508        WILSON'S  QUARTEK  CENTURY  IN  PHOTOGRAPHY. 

227.  It  may  be  that,  by  their  help,  we  are  led  one  step  further  in  the  pro- 
duction of  photographs  in  colors,  but  the  sanguine  photographer  must  not 
confuse  color-tone  with  color-production. 

gallol,  and  sodium  carbonate  and  sulphite,  with  a  little  bromide.  The  ordinary  stock 
solutions  of  pyrogallol  do  not  give  good  results.  In  all  cases  development  takes  place 
quickly,  and  there  is  a  tendency  to  fog. 

It  is  found  necessary  to  use  a  yellow  screen  in  order  to  get  the  best  results,  notwith- 
standing the  behavior  of  the  plates  to  the  spectrum  (?),  and  a  tank  containing  a  solution 
of  potassium  bichromate  (1 : 1000)  or  a  solution  of  picric  acid,  or,  better,  a  glass  plate 
coated  with  gelatine  dyed  with  picric  acid,  answers  satisfactorily. — C.  H.  BOTHAMLEY. 

227.  In  our  experiments  with  erythrosin,  cyanin,  and  azalin  we  find  that  plates  washed 
with  the  first-named  substance  are  most  sensitive  to  yellow,  and  the  greater  the  quantity 
of  blue  in  the  light  used,  this  yellow-sensitiveness  of  the  erythrosin  plate  decreases  in 
the  same  ratio  as  that  of  the  ordinary  plate  increases,  and  inversely. 

Mr.  Schumann  gives  a  table  showing  the"  difference  in  the  sensitiveness  of  blue  and 
yellow  in  plates  obtained  by  different  processes,  viz. : 

Yellow-sen.      Blue-sen. 

Pure  black  silver  gelatine      .....  0.0  1.00 

This  washed  in  iodepsin     .....  3.6  1 .01 

"           "          erythrosin.         .         .                 .  15.6  1.67 

"            "          cyanin 15.6  0.00 

Cyanin  is  a  coloring  material  discovered  by  Mr.  V.  Schumann,  of  Leipzig.  Its  use 
excited  considerable  controversy  among  photographers,  and  was,  at  first,  attended  by 
some  difficulty  owing  to  a  certain  dimness  an'd  some  spots  which  appeared  on  plates 
washed  in  it ;  but  accurate  directions  for  its  application  now  given  by  its  inventor  make 
it  of  greater  benefit,  and  permit  excellent  results.  In  an  orange-red  sensitiveness,  the 
cyanin  plate  surpasses  every  other  color-sensitive  plate,  not  even  excepting  the  azalin 
plate. 

Since  the  erythrosin  plate  is  deficient  in  this  very  red-orange-sensitiveness,  a  combina- 
tion of  cyanin  and  erythrosin  produces  very  satisfactory  results. 

Azalin,  another  coloring  substance,  was  brought  out  in  1884  by  Prof.  Vogel — or, 
rather,  plates  sensitized  with  it  were  manufactured  in  that  year.  This  dye,  in  an 
alcoholic  solution  and  in  a  concentration  of  about  1 :  500,  is  a  deep  carmine  (carmoisin) 
red  fluid  with  an  active  reddish-brown  flow. 

Chinolin  red  is  a  dye  discovered  by  E.  Jacobsen,  of  Berlin,  in  1882.  A  mixture  of  the 
two,  cyanin  and  chinolin,  in  the  proportion  of  1 : 10,  will  correspond  to  azalin.  Let  1  gr. 
chinolin  red  dissolve  in  500  c.  cm.  alcohol.  To  this  add  50  c.  cm.  of  a  solution  of  1  gr. 
cyanin  and  500  c.  cm.  alcohol. — MALLMAN  and  SCOLIK. 


CHAPTER   XXIII. 

PHOTO-ENG  RAVING. 

228.  THE  method  of  applying  photography  to  the  production  of  printing- 
blocks  to  be  used  with  type  in  the  printing  press  is  commonly  known  as 
photo-engraving  or  autoglyph. 

It  is  employed  not  only  by  the  daily  newspapers  for  their  somewhat  crude 
illustrations,  but  is  rapidly  reaching  a  place  in  the  magazines  and  books  which 
makes  it  a  fierce  compeer  of  wood-engraving. 

The  classes  of  results  may  be  known  as  "  line  "  and  "  half-tone,"  the  latter, 
of  course,  being  the  superior. 

229.  The   "swelling"   or  photo-relief,   the   "etching,"   and    the    "photo- 
electrotype"  processes,  with  their  modifications,  are  the  ones  most  used.     For 
"half-tone"  subjects   a  good   negative  direct  from   nature  will  serve  every 

229.  As  is  known,  one  of  the  chief  requisites  for  its  proper  chemical  reproduction  is 
that  it  should  exhibit  deep  black  lines,  and  a  pure  white  ground.  By  the  usual  method 
of  bleaching  photographic  prints  with  bichloride  of  mercury,  it  often  happens  that,  in 
spite  of  every  precaution,  the  whites  of  the  picture  appear  yellow  or  brownish-yellow,  a 
circumstance  which  greatly  increases  the  difficulty  of  making  a  proper  negative.  To 
overcome  this  fault,  Mr.  W.  Bode  recommends  the  following  receipt :  Distilled  water,  9 
parts ;  nitrate  of  silver,  1  part.  When  the  silver  has  dissolved,  pour  three  parts  of  the 
whole  into  a  glass,  and  add  ammonia  to  it  until  the  oxide  of  silver  which  has  formed 
dissolves,  and  the  solution  becomes  once  more  clear.  Then  pour  this  back  into  the  other 
six  parts.  If  oxide  of  silver  forms  again,  it  can  be  run  off  from  the  bottom  of  the  vessel, 
or  it  can  be  poured  out  and  filtered.  Use  only  good,  salted  paper.  Print  until  all  the 
details  are  out,  yet  not  too  deep,  then  wash  the  print  with  cold  water  until  it  is  red. 
When  the  residue  of  silver  is  completely  washed  out  by  frequent  changes  of  water,  the 
print  must  be  fixed  in  a  solution  of  soda,  say  equal  parts  of  hypo  and  of  double  carbonate 
of  soda.  Let  it  stay  in  this  solution  ten  to  twelve  minutes,  then  wash  it  many  times  in 
clear  water  and  then  mount  it. 

Since  the  picture  will  only  keep  for  a  few  days,  the  drawing  should  be  made  as  soon  as 
the  print  is  dry.  The  bleaching  material — a  solution  of  thirty  grains  of  bichloride  of 
mercury  in  one  litre  of  alcohol — should  be  poured  over  the  picture  in  the  same  way  as 
collodion.  In  a  quarter  of  an  hour  the  drawing  can  be  had  on  pure  white  paper,  and 
does  not  show  a  vestige  of  a  photographic  picture. — Photo.  Archiv. 

(509) 


510         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

purpose.  For  line  work  a  pen  drawing  must  be  made,  and  from  it  a  negative 
for  the  photo-engraving.  For  this  latter  purpose  the  drawing  may  be  made 
directly  upon  the  photograph,  and  then  the  parts  of  the  original  not  wanted 
are  bleached  away  so  that  only  the  drawing  remains.  The  photo-print  should 
be  upon  arrowroot  paper,  not  toned,  but  well  fixed  in  a  thoroughly  fresh 
solution  of  hyposulphite  of  soda.  When  dried  the  drawing  may  be  made 
with  Higgins's  waterproof  American  India-ink.  Now  immerse  the  picture  in 
a  bath  of  bichloride  of  mercury  and  alcohol,  and  allow  it  to  remain  there  until 
thoroughly  bleached.  Rinse  very  carefully  in  clean  water  and  allow  it  to  dry 
spontaneously.  The  drawing  only  remains  ready  for  reduction  to  the  desired 
size. 

230.  Experience  alone  can  teach  the  photo-engraver  how  to  succeed  with  the 
rest  of  the  process.  I  can  only  give  him  hints.  In  every  case  the  negative 

230.  I  will  illustrate  the  difference  between  the  three  processes  for  newspaper  work  by 
diagrams  on  the  blackboard,  showing  a  section  of  line,  and  the  steps  taken  in  each 
process  toward  its  production. 

Fig.  383  shows  the  several  stages  in  the  photo-relief  method.  First  the  negative  film 
is  brought  in  contact  with  the  sensitized  gelatine,  when  the  latter  is  exposed  to  light, 

FIG.  383.  FIG.  384.  FIG.  385. 


SWmZCO  GCLATin 


after  which  the  gelatine  which  has  been  so  exposed  is  placed  in  a  tray  of  water.  The 
portions  unhardened  swell ;  then  a  cast  is  taken  in  a  waxy  composition,  from  which  is 
made  a  plaster-ot-Paris  mould,  in  which  to  cast  a  type-metal  stereotype,  the  peculiarity 
of  the  resulting  line  being  that  the  corners  of  the  line  are  slightly  rounded.  For  book 
and  magazine  printing,  where  the  press  cylinder  turns  perfectly  true,  and  time  can  be 
given  to  the  process  of  overlaying,  in  the  hands  of  an  artistic  printer  this  line  with  the 


PHOTO-ENGBAVING.  511 

must  be  fully  intense,  and  exceeding  care  taken  in  every  stage  of  the  manipu- 
lation. 

231.  The  negative  secured,  if  the  "swelling"  method  is  to  be  followed 
proceed  as  follows :  Make  a  gelatine  relief  as  in  the  carbon  process  or  as 

rounded  face  can  be  taken  advantage  of  to  produce  a  light  or  heavy  line,  according  to 
the  pressure  of  the  paper  on  it  during  the  operation  of  printing. 

With  the  photo-electrotype  line,  which  is  produced  by  the  action  of  light  on  a  sheet 
of  sensitized  gelatine,  as  in  the  photo-relief  process,  the  unhardened  gelatine  is  washed 
out  with  a  soft  brush  and  a  tepid  solution,  leaving  the  portions  acted  on  by  the  light  in 
relief.  From  this  an  electrotype  is  made  in  the  usual  way. 

The  face  of  the  line  produced  by  this  process  is  the  reverse  of  the  photo-relief  line — 
that  is,  it  is  concave  where  the  other  is  convex,  the  corners  being  sharp  and  highest 
where  the  wear  is  greatest.  This  makes  the  most  serviceable  plate  for  newspaper  work, 
giving  a  square,  honest  line  at  each  impression. 

Figs.  384  and  385  illustrate  the  various  steps  of  the  zinc-etching  process.  A  plate  of 
zinc  is  coated  with  a  film  of  albumen  sensitized  with  bichromate  of  ammonia.  After  the 
exposure  to  light,  the  plate  is  rolled  with  a  fatty  ink,  then  the  unhardened  albumen  film 
is  washed  away,  leaving  the  ink  only  on  the  lines,  protecting  them  from  the  action  of 
the  acid  in  which  the  zinc  plate  is  immersed.  After  a  slight  etching,  the  plate  is 
removed  from  the  acid  and  dried,  then  powdered  dragon's-blood  is  brushed  against  the 
sides  of  the  line.  The  zinc  plate  is  heated,  the  powdered  dragon's-blood  combines  and 
forms  a  resinous  coating,  which  protects  the  sides  of  the  line  from  the  further  action  of 
the  acid.  This  process  of  drying,  dusting  with  the  powder,  heating,  and  etching,  is 
repeated  many  times,  till  the  requisite  relief  is  obtained,  the  finishing  line  showing,  as  in 
the  diagram,  a  series  of  steps  down  the  side  corresponding  to  the  number  of  etchings. — 
S.  H.  HOEGAN. 

231.  Dissolve  1  ounce  of  Coignet's  Gold  Label  Gelatine  in  6  ounces  of  distilled  water, 
and  to  1  ounce  of  this  solution  add  30  grains  of  nitrate  of  silver,  previously  dissolved  in 
\  an  ounce  of  distilled  water ;  to  the  other  5  ounces  of  solution  of  gelatine,  add  2  ounces 
of  a  saturated  solution  of  bichromate  of  potass,  (saturated  at  a  temperature  of  60°  F.), 
and,  whilst  still  warm,  add  to  it  the  gelatine  solution,  containing  the  nitrate  of  silver 
(which  solution  has  also  been  kept  warm);  stir  up  well  with  a  glass  rod  during  addition, 
and  continuing  the  stirring,  add  100  grains  of  crystallized  calcium  chloride ;  and  when 
dissolved,  add  150  grains  of  glycerine,  which  must  also  be  thoroughly  mixed  with  the 
gelatine  solution. 

Level  a  glass  plate  (J-  inch  thick,  and  rather  coarsely  ground  with  emery  powder),  and 
pour  over  it  as  much  of  the  above  solution  as,  when  dry,  will  leave  a  film  about  the  thick- 
ness of  thin  writing  paper.  Dry  in  the  dark. 

When  dry,  expose  under  a  negative  for  about  three  hours,  or  until  all  details  of  the 
picture  are  fully  visible  when  viewed  by  transmitted  light. 

After  exposure,  immerse  in  clean  cold  water  until  those  portions  of  the  film  acted 
upon  by  light  filtered  through  the  negative  become  granulated  or  reticulated ;  the  plate 
is  then  removed  from  the  water,  drained,  and  remainder  of  moisture  removed  by  blotting- 
paper. 


512        WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHS. 

described  further  on.  AfteY  thoroughly  dry,  make  a  plaster  cast  from  this 
relief,  and  from  that  again  the  stereotype  plate.  Some  manipulators  use  wax 
instead  of  plaster. 

232.  This  method  is  being  abandoned,  however,  for  the  zinc-etching  process, 
which  is  less  complicated  and  more  expeditious.  Some  may  make  the  objection 
to  it,  that  it  "  requires  more  head  to  work  it "  than  the  other.  This  cannot  be 
denied.  The  relief  is  made  as  described  below,  and  then  transferred  to  a  zinc 
plate.  There  it  is  built  up  by  a  series  of  applications  of  lithographic  ink  and 

A  mould  is  now  taken  from  the  film  in  gutta-percha  or  sulphur,  and  from  this  mould 
a  block  is  made  by  electrotyping  or  stereotyping. — MAX  PRETSCH. 

232.  This  is  a  good  zinc-etching  process.  The  reverse  negative  should  be  made  on  a 
perfectly  level  plate,  so  as  to  get  the  nearest  possible  contact  with  the  zinc  plate.  To 
obtain  a  good  result  it  is  necessary  that  the  negative  should  show  every  line  and  every 
point  with  the  greatest  sharpness.  Give  attention  to  the  exact  time  of  exposure.  If 
the  exposure  be  too  long,  the  delicacy  will  disappear  in  the  development  and  in  the 
strengthening  of  the  negative.  As  a  general  rule,  the  development  should  be  stopped  as 
soon  as  the  image  appears  distinctly  and  with  all  its  details,  after  which  the  plate  is 
washed,  fixed  with  cyanide  of  potassium,  and  then  again  thoroughly  washed ;  afterward 
the  following  solution  is  poured  on  the  plate,  on  which  it  is  allowed  to  remain  until  the 
pellicle  becomes  almost  white:  Sulphate  of  copper,  1  ounce;  bromide  of  potassium,  1 
drachm  ,-  water,  8  ounces.  After  which  the  plate  is  thoroughly  rinsed  and  plunged  into 
a  solution  of  one  part  of  nitrate  of  silver  to  ten  parts  of  water.  The  plate  instantly 
becomes  black.  If  upon  the  application  of  the  sulphate  of  copper,  the  fine  lines  should 
fill  up,  it  is  because  the  negative  has  been  overexposed.  If  the  exposure  has  been  good, 
all  the  white  portions  (of  the  paper)  will  be  opaque,  whilst  all  the  lines  and  outlines  will 
be  perfectly  transparent. 

The  negative  finished,  take  a  well-polished  zinc  plate  of  the  required  size,  which  is 
again  repolished  with  finely  powdered  pumice-stone  and  water.  After  washing  the 
plate  in  clear  water  in  a  dark  room,  pour  the  following  solution  on  the  zinc  plate  whilst 
still  damp  :  Place  the  white  of  an  egg,  beaten  to  a  froth,  in  six  ounces  of  water,  to  which 
add  thirty  grains  of  bichromate  of  potash  finely  pulverized,  which  are  allowed  to. melt; 
then  filter  the  whole.  The  first  quantity  of  the  solution  poured  on  the  plate  is  thrown 
away,  but  the  solution  used  afterward  is  returned  to  the  bottle  to  serve  again.  The  plate 
is  dried  by  holding  it  by  one  corner,  inclined  over  an  oil  lamp  or  gas  jet,  care  being 
taken,  however,  that  it  shall  not  become  heated.  When  it  is  dry  and  cold  the  plate  is 
ready  for  exposure.  Now  place  the  negative,  the  front  in  contact  with  the  prepared  zinc 
plate  in  a  pressure  frame  similar  to  those  used  by  photographers.  By  means  of  springs 
a  good  pressure  is  obtained,  so  that  the  negative  presses  closely  to  the  zinc  plate ;  then 
expose  the  frame  to  the  light  for  from  two  to  four  minutes  according  to  the  nature  of  the 
work.  It  is  preferable  to  make  the  exposure  in  full  sunlight.  The  frame  is  now  brought 
back  to  the  dark-room  and  the  zinc  plate  rolled  with  a  good  lithographic  roller,  finely 
grained,  with  good  transfer  ink,  not  too  thin;  the  fatter  the  ink,  the  better  the  result 
will  be. 


PHOTO-ENGRAVING.  513 

powdered  resin,  until  the  proper  depth  is  attained,  the  degree  of  which  must  be 
judged  by  the  manipulator,  who,  in  turn,  is  guided  by  the  subject  in  hand. 

233.  The  taste  will  direct  to  both  grain  and  line  according  to  circumstances. 
There  is  no  royal  road  to  success  in  this  department.  An  exact  and  expensive 
plant  is  required  ;  artistic  feeling  is  essential ;  a  stereotype  furnace  is  required, 
unless  one  be  convenient  to  the  studio. 

Thus  far  experts  have  kept  their  information  closely  to  themselves ;  but  I 

After  having  inked  the  plate  in  this  manner  it  is  placed  in  a  dish  filled  with  clear 
water,  and  the  superfluous  ink  on  the  non -exposed  parts  is  removed  by  means  of  a  cotton 
cloth  well  soaked  in  water.  This  should  be  done  very  slowly  and  carefully,  giving  to 
the  hand  a  motion  in  small  circles  commencing  at  the  corners,  advancing  slowly  over  the 
whole  surface,  as  the  too  rapid  motion  would  partially  destroy  the  sharpness.  If  the 
time  of  exposure  has  been  correct,  the  image  will  develop  itself  easily ;  if  there  has  been 
overexposure  the  ink  will  stick  to  the  plate,  and  cannot  be  easily  removed,  which  offers 
more  or  less  danger  of  spoiling  the  work.  If  the  time  of  exposure  has  not  been  suffi- 
ciently long,  the  result  will  certainly  be  defective,  especially  in  the  plates  that  have 
great  delicacy.  In  both  cases  it  is  far  better  to  repolish  the  plate  with  a  strong  solution 
of  potash  and  finely  powdered  pumice-stone,  wash  in  water,  and  begin  the  operation 
anew. 

By  careful  attention  to  what  has  been  said  and  a  little  practice,  the  operator  will  soon 
be  able  to  determine  the  necessary  time  of  exposure.  After  having  removed  the 
superfluous  ink,  the  plate  is  cleaned  in  water  and  dried  by  means  of  heat.  When  cooled 
it  is  dusted  over  with  finely  powdered  resin,  well  rubbed,  and  the  excess  removed.  The 
plate  is  then  heated  until  the  resin  begins  to  melt.  This  is  shown  by  the  slightly  darker 
tint  of  the  plate;  after  etching,  the  plate  is  again  inked,  dusted  with  resin,  heated,  and 
the  operation  continued  until  the  necessary  thickness  or  depth  is  obtained. 

233.  This  grain  is  produced  either  on  a  film  of  bichromatized  gelatine  or  on  one  of 
gelatino-bromide,  by  means  of  a  reticulation.  For  films  of  bichromatized  gelatine,  the 
plate,  coated  as  for  printing  with  fatty  ink,  is  dried  at  a  low  temperature,  21°  C.  (70°  F.) 
exposed  under  a  negative,  washed  with  great  care,  then  plunged  into  a  mixture  of — 
sulphuric  acid,  2  grammes  (31  grains),  and  water,  310  grammes  (10  ounces),  for  thirty 
minutes.  Wash  in  several  waters,  the  plate  being  drained  each  time,  and  place  in  a 
saturated  solution  of  alum  for  fifteen  or  twenty  minutes,  then  repeat  the  washing.  The 
plate  is  now  placed  in  a  dish  containing  water  heated  from  32°  to  38°  C.  (89°  to  100°  F.), 
just  enough  to  cover  it.  At  the  expiration  of  ten  minutes  the  plate  should  present  a 
uniform  matt  appearance ;  this  is  the  time  to  withdraw  it  and  plunge  it  into  cold  water. 
For  gelatino-bromide  films  operate  in  the  same  manner,  except  as  regards  the  exposure 
and  the  development.  If  a  grained  negative  or  transparent  print  is  wanted,  it  is  best  to 
give  a  rather  longer  exposure  and  develop  rapidly  to  obtain  much  detail  without  too 
much  density.  Different  grains  are  obtained  by  adding  to  the  acid  mixture  other  acids, 
such  as  citric,  tartaric,  nitric,  chlorhydric,  or  in  mixing  the  acid  with  an  alum  solution, 
and  by  varying  the  time  of  contact.  Great  care  should  be  taken  to  have  the  film  of 

33 


514:         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

am  gradually  drawing  information  from  all  sources  and  countries,  which  will 
enable  me  presently  to  publish  a  complete  manual  of  instruction. 

For  examples  of  photo-engraving,  I  need  only  point  to  the  beautiful  pictures 
in  Chapters  IX.  and  X.,  to  the  lovely  pictures  in  Chapter  XXII. ,  and  on 
every  side  and  in  every  home. 

234.  The  pictures  by  Mr.  Ives's  process,  in  Chapter  XXII.,  are  by  a  process 
which  has  not  been  excelled  by  the  highest  of  its  family.  Kindred  results  are 
produced  in  Europe,  and  are  known  as  "  Meiseubach  " — here  as  "Autoglyph  " 
— but  they  are  by  processes  entirely  different  from  Mr.  Ives's. 

equal  thickness,  otherwise  the  grain  would  be  unequal.  A  thick  coating  gives  a  stronger 
grain  than  a  thin  one. — Paris  Moniteur. 

234.  The  Meisenbach  process  is  described  as  follows :  A  transparent  plate  is  etched  or 
stippled  in  parallel  lines.  A  transparent  positive  is  made  of  the  object,  the  two  plates 
are  joined,  preferably  face  to  face,  and  from  the  combined  plates  a  definite  negative  is 
photograved  in  the  ordinary  way.  In  order  to  cross-hatch  and  break  the  lines  of  the 
shading,  the  hatched  or  stippled  plate  may  be  shifted  once  or  twice  during  the  produc- 
tion of  the  negative.  The  photographic  negative  thus  obtained  may  be  either  applied 
direct  to  a  zinc  plate,  or  a  lithographic  transfer  may  first  be  made  in  the  usual  manner, 
and  the  plate  subsequently  bitten  by  acid  to  form  a  block  in  relief.  Considerable  im- 
portance is  attached  to  the  shifting  of  the  hatched  gr  stippled  plate,  this  being  the  part 
of  the  process  which  is  especially  sought  to  be  protected  by  the  patent. 

The  following  makes  a  very  good  fusible  alloy.  It  melts  at  160°  F.,  and  can  conse- 
quently be  used  for  moulding  gelatine  reliefs  used  in  photography :  Bismuth,  47.38  per 
cent. ;  cadmium,  13.29  per  cent. ;  lead,  19.36  per  cent. ;  tin,  19.37  per  cent. — E.  L.  W. 

Prints  on  Wood. — The  block  of  wood  receives  first  a  white  layer,  consisting  of  a  solu- 
tion of  one  part  gelatin  and  eighty  parts  water,  mixed  with  some  white,  moist  water 
color,  which  is  laid  on  with  a  broad  brush.  After  drying,  the  following  solution  is  laid 
on  with  a  brush,  in  broad  strokes :  A.  Red  prussiate  of  potash,  6  grammes ;  water,  50 
grammes.  B.  Ferric  citrate  of  ammonia,  7  grammes ;  water,  50  grammes.  Mix  both 
solutions  in  the  dark,  and  guard  the  same  against  the  influence  of  the  light.  The  wood- 
block which  is  coated  with  the  solution  is  dried  in  the  dark,  and  it  is  to  be  lighted  under 
the  negative  from  ten  to  twelve  minutes  in  the  sun.  Then  it  is  wiped,  in  the  dark-room, 
with  a  soft,  wet  sponge,  when  a  beautiful  dark -blue  picture  will  appear  which  does  not 
crack  off  in  cutting. 

To  produce  a  red  picture,  dissolve  from  four  to  six  grammes  of  sulphuric  deutoxide  of 
uranium  in  one  hundred  grammes  of  diluted  solution  of  gelatine  or  gum,  and  coat  the 
wood  block  with  it,  in  the  dark.  After  drying,  light  the  same  from  ten  to  twenty 
minutes  under  the  negative  in  the  sun ;  then  wipe  it  well  with  a  wet  sponge,  and  quickly 
lay  on,  with  a  clean,  moist  sponge,  a  solution  of  four  grammes  red  prussiate  of  potash  in 
one  hundred  grammes  of  water,  which  operation  will  cause  the  picture  to  appear  at  once. 
When  the  whole  picture  is  visible  the  chemicals  have  to  be  washed  out  with  a  fresh  wet 
sponge.  In  case  the  picture  has  been  copied  too  dark,  pour  a  few  drops  of  sulphuric 
acid  into  water,  and  brighten  up  the  sains  with  it. — Photogmphische  Archiv. 


CHAPTEK    XXIY. 


FIG.  386. 


LANTERN   SLIDES   AND   TRANSPARENCIES. 

235.  I  MUST  make  the  chapter  on  this  most  delightful  of  all  photographic 
productions,  brief,  and  confine  what  I  say  to  the  processes  which  are  most 
convenient  and  practical  for  my  readers. 

The  most  important  uses  made  of  glass  transparencies  are  for  decoration  and 
for  the  magic  lantern.  The  technical  quality  for  these  two  purposes  is  by  no 
means  the  same.  Though  an  impression  exists  that  a  transparency  which 
appears  pleasing  to  the  eye  when  viewed  by  transmitted  light  is  all  one  could 
wish  for  the  lantern,  it  is  not  true.  A  transparency  for  window  purposes  or 
for  a  screen  should  be  full  of  detail,  and  color  given  to  every  part  of  the  film  ; 

235.  By  the  wet  plan  the  positive  can  be  made.any  size  desired,  either  larger  or  smaller 
than  the  negative.  To  make  wet  positives  it  is  necessary  to  have  two  cameras  placed 
front  to  front,  or  one  regular  camera  box, 
with  an  extension  attached  to  the  front,  so 
that  it  can  be  adjusted  to  the  size  wanted. 
My  own  (Fig.  386)  is  arranged  in  the  fol- 
lowing -manner :  A  camera  box,  8  x  10, 
having  a  movable  front,  is  used  for  exposing 
the  plate.  I  shall  call  it  No.  1.  On  the 
edge  of  the  front,  extending  up  and  down, 
on  both  sides,  is  screwed  a  piece  of  wood, 
making  a  groove  into  which  the  extension, 
or  camera  box  No.  2,  slips,  having  a  flange 
on  its  edges  corresponding  to  the  grooves  in 
No.  1. 

Box  No.  2  is  made  with  a  large  opening 
in  the  front,  or  part  joining  No.  1.  The 
upper  end,  instead  of  having  a  grooved  glass, 
has  an  opening  arranged  to  fit  a  6',  x  8£ 
negative,  with  a  dark  slide  immediately  behind.  This  box  has  a  bellows  and  rack 
adjustment  similar  to  any  camera ;  in  size  it  must  be  made  to  draw  out  at  least  thirty 
inches.  To  put  the  boxes  in  working  order,  take  off  the  movable  joint  of  No.  1,  on 
which  the  lens  is  fastened;  then  push  them  together,  joint  to  joint;  pull  out  the  dark 

(515) 


516         WILSON'S  QUARTER  CENTURY  IN  PHOTOGRAPHY. 

while  a  magic-lantern  slide  needs  to  be  much  more  transparent  in  the  shadows, 
and  the  lights  should  be  as  near  clear  glass  as  is  possible.  For  this  reason, 
"  dry  "  lantern  slides  are  not  as  good  as  "  wet." 

The  proof  of  a  good  slide  is  not  the  sight,  or  one's  color  taste,  but  the  effect 
of  its  projection  upon  the  screen. 

In  the  exposure  and  in  the  development  the  utmost  precision  and  care  must 
be  practised. 

All  the  beauty  of  the  glass  picture  may  be  spoiled  in  the  mounting  and 
finishing.  A  light-colored  obtrusive  border  or  mat  should  never  be  used.  A 
gilt  line  upon  a  black  mat  and  an  absolutely  black  border  for  slides  is  best. 
Window  transparencies  must  be  backed  with  Hance's  "ground-glass  substitute" 
or  ground  glass. 

slide  of  No.  2,  and  adjust  the  front  of  No.  1  (containing  the  lens)  in  its  position.  Then 
place  the  negative  in  the  frame  of  No.  2,  inclining  the  boxes  so  that  the  line  of  vision 
will  strike  the  sky  or  any  white  object. 

I  use  the  sky,  fastening  the  boxes  on  a  copying  board  seven  feet  long,  raising  the  upper 
end  so  that  the  negative  is  clear  of  the  line  of  houses  or  trees,  which  can  be  readily  done 
by  looking  through  the  ground  glass.  If  possible,  use  a  north  exposure ;  and  do  not  let 
the  sun  strike  the  negative.  The  leng  in  No.  1  must  always  be  uncovered,  using  the 
slide  behind  the  negative  as  a  covering. — J.  C.  BROWNE. 

Transparencies  can  be  made  the  same  size  of  negative  by  contact  and  exposure  to 
artificial  light,  or  enlarged  or  reduced  in  the  camera  by  day-light,  with  equal  perfection 
in  result.  To  make  lantern  slides  by  contact,  place  one  of  the  Keystone  thin  crystal 
glass  transparency  plates  over  the  negative  in  printing-frame,  lay  a  piece  of  dark,  soft 
material  over  it,  close  down  the  back,  and  expose  to  the  dear  light  side  of  a  Multum  in 
Parvo  Lantern,  or  other  light,  for  ten  to  fifteen  seconds  at  a  distance  of  twenty  inches 
from  the  flame.  Use  the  ferrous  oxalate  developer.  Let  the  development  continue  until 
the  blacks  look  quite  strong,  and  detail  plainly  showing  in  the  high  lights;  wash  off 
developer  thoroughly  before  fixing ;  use  fresh  hypo  solution ;  when  fully  cleared,  wash 
for  half  an  hour,  then  immerse  in  alum  bath  for  five  minutes :  Chrome  alum,  \  ounce ; 
citric  acid,  \  ounce ;  water,  36  ounces.  Wash  for  half  an  hour,  then  carefully  go  over 
the  surface  with  a  soft  camel's  hair  brush,  or  pledget  of  cotton,  to  remove  any  particles 
of  dirt ;  place  in  rack  to  dry.  When  dry,  cover  with  matt  and  clean  crystal  glass  cover, 
and  bind  with  binding  strip. 

The  tone,  both  of  lantern  and  large  transparencies,  can  be  varied  from  a  warm  brown 
to  a  velvety  black.  .Increased  exposure  and  weaker  developer  (adding  water)  with  more 
bromide  gives  warm  brown  tones.  Short  exposure  and  stronger  (undiluted)  developer 
gives  dark  tones.  The  same  solutions  given  for  negative  intensification  can  also  be  used 
for  toning  transparencies. — JOHN  CARBUTT. 


INDEX. 


A  BERRATION  OF  LENSES,  45,  61 
XX    Ability,  selective,  147 
About  lenses,  33 
Accelerator  for  dry  plates,  343 
Actino-hydrometer,  the,  280 
Action  of  chemical  light,  22,  30 

of  different  forms  of  developer,  417 

of  diffused  light,  223 
Air,  a  disturber,  244 
Albumen,  374 

paper,  printing  on,  442 

dish  for  silvering  the,  449 
plan1  for  drying  the,  450 
silvering  the,  448 
varied,  toning  of,  452 

the  important  substance,  445 
Albumenizing  glass,  288 
Alcohol  for  drying  plates,  409 
Alcoholic  solutions  of  gelatine,  409 
Alloy  for  photo-engraving  plates,  514 
Alum  in  emulsions,  417 

process,  demons',  460 
American  films,  manipulation  of,  426 

glass  house,  typical,  77 
Ammonia  developer,  sulphite  of,  357 
A  new  method  of  development,  351 
Angle  of  the  lens  determines  size,  33 

of  view  of  lenses,  44 
Aniline  process,  the  Willis,  493 
Animal  photography,  200 
Annoyances,  negative,  302 
Anthony's  bromo-gelatine  paper,  printing 

on,  479 

Apparatus  for  enlarging,  Beach's,  485,  486, 
487 

for  making    emulsion,   315,   316,   319, 

320,  321 

Application  of  art  principles,  141 
Aquatints,  printing  frame  for,  465 
Archer,  Scott,  20 
Architectural  views,  230 
Aristotype  paper,  printing  on,  475 
Art,  beginning  of,  181 


Art,  but  selections  from  nature,  150 

come  in,  where  does,  1 78 

feeling  in,  154 

individuality  in,  151 

light  and  shade,  163 

principles,  application  of,  141 

rules  fundamental  in,  161 

the  highest  is  felt,  153 

under  obligation  to  photography,  175 
Artificial  clouds  in  outdoor  views,  191 
•  light,  portraiture  by,  412 

negatives  by  etching,  440 
Artist,  the  true,  176 
Artistic  sentiment  or  conception,  159 

sight,  142 
Artist's  estimate,  an,  175 

intention  and  meaning  of  the,  158 
Astigmation  of  lenses,  61 
Atmosphere  in  outdoor  views,  186 
Atmospheric  influence  on  chemicals,  242 
Au  deux  crayons,  printing,  469 
Auxiliary  exposure,  220 


BABY  photography,  the  new,  179 
shutter,  Coddington's,  137 
Bachrach's  developer,  354 
Background,  Motes' circular,  120 

hints  on  the  use  of  the,  125 

influence  of  the,  124 

Kurtz's  cone,  122 

revolving,  123 

Salomon's  concave,  121 
Balagny's  flexible  gelatine  bromide  plate,430 

"instantaneous"  carb.  soda  developer, 

379 

Balances,  have  correct,  277 
Bath,  boiling  the,  308 

excess  of  iodide  in  the,  303 

on  proper  strength  of  fixing,  41 6 

purification  of  the,  307 

solution  for  negative  nitrate,  291 
"  Berlin  "  pictures,  printing,  470 

(517) 


518 


INDEX. 


Best  light  is  sunlight,  228 

Blanchard  brush,  the,  289 

Bleaching  process  for  photoengraving,  510 

Blisters  in  prints,  459 

"Blue"  printing,  491 

Blurring  in  emulsion  plates,  413 

Board,  Benecke's  sight,  128 

Smith's  copying,  1 28 
Bottle,  Stebbing's  dropping,  271 
Brilliant  negatives,  to  obtain,  292 
Bromide,  choice  of,  413 

function  of  an  excess  of,  415 

of  silver,  22 

sensitiveness  of,  417 
Brooks'  developer  holder,  267 
Brush,  mounting,  473 

the  Blanchard,  289 
Building  up  the  metallic  image,  23 
Burnisher,  lamp  for  heating  the,  260 


/CAMERA  contrivances,  135 
\J     discovery  of  the,  18 

for  medallions,  137 

multiplying,  with  the,  136 

obscuro,  the,  18 

position  of  the,  118 

Spencer's  copying,  129 

the,  21 

the  first,  18 

the  pinhole,  61 

vignetting  in  the,  135 
Car,  photographic,  model,  98 
Carbon  printing,  501 

as  gelatino-bromide,  417 
Carbonate  of  soda  developer,  379 
Carrier  for  film  negatives,  433,  424 
Centring  the  lens,  62 
Chandler's  siphon,  273 
Charges  against  portrait  photography,  148 
Charles,  Prof.,  19 

shadow  experiment,  19 
Chemical  action  of  light,  22 

focus  of  lenses, '63 

retouching,  436 
Chemicals,  atmospheric  influence  on,  242 

concerning,  239 

contamination  of,  258 

influence  of  heat  on,  242 

pure,  242 

tests  for  purity  of,  247 
Chevreul,  portraits  of,  180 
Chiaro-oscuro,  169 
Children's  pictures,  making,  92 
Chloride  of  silver,  21 


Chloride,  function  of  an  excess  of,  415 
Chloro-bromide  emulsion,  311 

-iodo-bromide  emulsion,  312 
Choice  of  lenses  for  landscape  views,  199 

of  bromide  for  emulsions,  413 
Chrome  alum  in  emulsion,  417 
Circular  background,  Motes',  120 
Cleaning  glass,  Root's  contrivance  for,  287 
Cleaning  off  old  films,  414 
Clear  spots  in  negatives,  394 
demons'  alum  process,  460 
Climb,  ability  to,  for  views,  187 
Clouds,  artificial,  191 

in  outdoor  views,  190 
Coarse-grained  negative  managing,  401 
Coating  emulsion  plates,  337 
Collodio  albumen  emulsion,  313 
Collodion,  289 

colored,  for  retouching,  435 

decanting,  275 

Fennemore's,  289 

process,  Archer's,  20 
Color  sensitive  photography,  504 
Colored  collodion  for  retouching,  438 
Composition,  163 

genre,  165 
Concave  background,  Salomon's,  121 

reflector,  Griswold's,  113 
Conception  of  a  picture,  203 

or  sentiment,  artistic,  159 
Concerning  chemicals,  239 
Cone  background,  Kurtz's,  122 
Conjugated  foci  of  lenses,  42 
Constitution  of  the  eye,  the,  323 
Contamination  of  chemicals,  258 
Contrivances,  camera,  135 

dark-room,  251 
i  Cooling  the  studio,  103 

contrivance,  Root's,  259 
Scotford's,  261 

emulsion  plates,  331 
Copying  board,  Benecke's,  128 
Smith's,  128 

camera,  Spencer's,  129 

table,  Hall's,  130 
Correct  perspective,  211 
Corrected  under  lenses,  64 

over  lenses,  64 
Correction  of  lenses,  46 
Counter  reflector,  Kurtz's,  114 
Curtain  stand,  Spencer's,  133 
Curtains  for  the  skylight,  105 
Curvature  of  field  of  lenses,  55 

lens,  39 
Cutting  the  paper,  446 


INDEX. 


519 


TV\  GUERRE,  20 
I J     Dark-room  contrivances,  251 
Dark-room,  illumination  of,  410 

lanterns,  255 

light  for  the,  250,  255 

model,  252 

sink,  251 

tanks  for  the  258 

ventilator,  254 
Davy,  Sir  Humphrey,  19 
Day,  beginning  the  manipulator's  249 
Decanting  collodion,  275 
Dense,  but  lacking  detail,  400 
Density,  reducing  the,  385 

too  great,  403 

want  of,  404 
Detail,  but  no  density,  400 

lack  of,  400 
Developer,  accelerator  for,  343 

alkaline  pyro,  all  in  one  solution,  347 

a  new  method,  351      • 

a  quick,  351 

a  universally  useful,  351 

Bachrach's,  354 

carbonate  of  soda,  349 

for  quick  plates,  379 

Edwards',  348 

ferrous  oxalate,  357 

for  overexposure,  343 

for  underexposure,  345 

handling  the,  343 

hydroquinone,  358 

hyposulphite  in  the,  410 

in  three  solutions,  348 

Monckhoven's,  356 

Newton's,  354 

par  excellence,  347 

potash  solution,  352 

pyro  and  carbonate  of  potash,  344 
solution,  352 

rationale  of  the,  355 

stock  solution,  352 

sulphite  of  ammonia,  357 

what  shall  we  use,  343 
Developing  cup,  270 

processes,  "  wet,"  296 

solution,  holder  for,  267 
Development  by  pressure,  241 

of  emulsion  plates,  314 

of  film  negatives,  425,  426 

of  the  negative,  295 

theory  of,  240 

Diamond  negative,  the,  440 
Diaphragm,  Towler's  sky,  192 

or  stop,  the,  65 


Diaphragm,  Zentmayer's  adjustable,  73 
Difficulties  and  drawbacks,  208 
Diffused  light,  action  of,  223 
Diffusion  of  focus,  60 
Direct  positives  in  the  camera,  412 
Dirty  fingers,  305 
Discovery  of  Daguerre,  20 
of  Niepce,  20 


Dishes 


of  photography,  the,  17 

les,  Latchmore's  method  of  emptying, 

274 

Stebbing's  method  of  emptying,  275 
Webster's  method  of  emptying,  274 
Disordered  bath,  treatment  of  a,  308 
Dispersion  of  lenses,  51 

of  light,  29 

Distance  and  elevation  for  landscapes,  195 
Distilled  water,  to  make,  263 
Distortion  of  lenses,  56 

correction  of,  59 

Doctoring  and  retouching  the  negative,  435 
Don't,  things  to,  406 
Draining  emulsion,  dry  plates,  332,  337 
Drapery,  lighting  white,  117 
Drawbacks  and  defects  in  printing,  458 
Drawings,  gelatine  reproduction  of,  412 
Dropping-bottle,  Stebbing's,  271 
Drying  albumen  paper  prints,  462 
apparatus  for,  339 
at  high  temperature,  333 
box  for  emulsion  dry  plates,  tempera- 
ture, 338 
emulsion,  dry  plates,  temperature,  333, 

409 

stand,  negative,  Green's,  279 
"Dry"  negative  making,  311 

plates,  development,  accelerator,  343 
development  of,  340 
draining  emulsion,  000 
relative  sensitiveness  of,  314 


EASELS    for    enlarging   bromp-gelatine 
paper,  484 

Eder's  ammonio-nitrate  emulsion,  322 
Edwards'  developer,  348 
Effect  produced  by  light,  60 
Emptying  dishes,  Latchmore's  method,  274 
Stebbing's,  275 
Webster's,  274 

Emulsion,  aids  to  working,  379 
alcoholic  solution  of,  409 
apparatus   for  making,  315,  316,  319, 

320,  321 
becomes  fluid,  397 


520 


INDEX. 


Emulsion,  boiling  the,  330 
bromo-gelatine,  327 
changes  of  gelatine  in  making,  324 
chloro-bromide,  311 
choosing  gelatine  for,  327 
coating  glass  with,  337 
collodio-albumen,  313 
cooling  and  washing  the,  331 
development  of,  340 
draining  the,  332 
Eder's  ammonio-nitrate,  322 
failures,  causes  of,  341 
flows  irregularly,  397 
frilling,  334 

iodo-chloro-bromide,  312 
is  full  of  air  bubbles,  397 
is  thin,  397 
made  at  high  temperature,  333 

at  low  temperature,334 
manufacture  of,  315 
Obernetter's  formulae  for,  371 
plates,  amount  of  iodide  in,  326 

developing  with  carb.  soda,  379 

drying  the,  337 

apparatus  for,  339 
box  for,  338 

exposure  of,  340 

fixing,  364 

frilling  of,  353 

washing,  364 

apparatus,  365,  366 
preliminary  bath  for,  342 
preparation  of,  374 

with  ammonia,  329 
refuses  to  set,  397 

sensitiveness  increased  by  heating,  329 
slow,  for  landscape  work,  318 
Spering's  rapid,  323 
temperature  at  drying,  333 
testing  the,  328 
to  secure  gradation  with,  117 
turns  brown  and  gray,  397 
Vogel's  stirring  apparatus  for,  323 
washing  the,  328,  335 

apparatus  for,  335,  336,  376 

Obernetter's  plan,  376 

tear  drops  on,  395 

white  powder  on,  396 
Wilson-Paget  prize,  368 
"ng,  photo-,  487 

alloy  for,  514. 

"  etching"  method,  512 

"  grain"  method,  513 

illustrated,  509,  510 

in  half  tone,  514 


Engraving,  photo-,  Ives'  process,  514 
Meiscnbach's  plan,  514 
"swelling"  method,  511 
Enlargements  on  bromo-gelatine  paper,  485 

hints  on,  483,  485,  486 
Enlarging  apparatus,  Beach's,  485,  48i3 
Equivalent  focus  of  a  lens,  to  find  the,  42 
Estimate  of  photography,  an  artist's,  176 
Etching,  zinc,  509,  512 
illustrated,  510 
Exact,  be,  245 
Exactitude  in  weighing,  277 
Expose,  when  to,  226 

how  to,  226 
Exposing  flap,  218 

shutters,  211,  231 

speed  of  the,  231 
Exposure,  or  the  question  of  time,  220 

a  matter  of  inspiration,  225 

auxiliary,  221 

influence  of-the  lens  on  the,  230 

latitude  in,  227 

long,  227 

no  rule  for,  225 
Expression  of  soul  in  art,  438 
Eye,  the,  32 

and  the  camera,  the,  32 

constitution  of  the,  32 

rest,  the,  127 


T71ABRICUS,  19 

JJ      Failures  with  emulsion  plates,  causes 

of,  341 

Feeling  in  art,  154 
Ferrotypes,  prism  for  reversing,  139 

multiplier,  Rawson's,  140 
Ferrous  oxalate  developer,  357 

solution,  restoration  of,  411 
"  Film"  carrier,  424 

development  of,  425 
illustrated,  423 
manipulation  of  the,  424 
negatives,  418 
preparation  of  the,  423 
Films,  American,  manipulations  of,  426 
intensification  of,  428 
manipulation  of  Thiebault,  429 
oxalate  developer  for,  427 
Thiebault's  support  for,  429 
Filter,  Garrett's  glass,  264 
Kurtz's,  265 
Platt's,  265 
to  make  a  glass,  264 
plaited,  263 


INDEX. 


521 


Filter,  Woodman's,  264 
Filtering  tray,  Vidal's,  284 
Filtration  of  water,  263 
Fingers,  dirty,  cause  of  stains,  305 
Fixing  bath,  strength  of,  416 

of  emulsion  plates,  364 

of  the  negative,  slow,  402 

relief  after,  416 

solutions,  action  of  the,  25 
poisonous,  26 

the  prints,  455 

the  "  wet"  negative,  298 
Fixing  tray  for  emulsion  plates,  364 
Flap,  exposing,  218 
Foci  of  lenses,  conjugated,  42 

to  find  the,  41 
Focus,  chemical  of  lenses,  63 

diffusion  of,  60 

equivalent,  to  find  the,  41 

test,  Chute's,  132 
Focussing  surfaces,  134 
Fog,  303,  373,  388 

general,  388 

green,  389,  399 

red,  389,  399 

to  remove,  389,  390 

yellow,  399 

Fogging  of  the  plates,  373,  398 
Foreground  studies,  205 
Formation  of  the  photographic  image,  22 
Foss's  sub-studio,  115 
Four-poster,  Hepworth's,  271 
Fox,  Talbot,  20 
Frilling  of  emulsion  plates,  334,  363,  390 

causes  of,  391 

Fuming  the  prints,  box  for,  464 
Fundamental  rules  in  art,  161 
Future  of  photography,  the,  17 


ri  ARRETT'S  filter,  264 
\JT  Gause's  siphon,  273 
Gelatine,  value  of,  preventing  precipitation, 

415 

Gelatino-bromide,  increasing  the  sensitive- 
ness of,  415 

keeping  qualities,  415 
General  fog  in  negatives,  388 
Genre  composition,  165,  168 
Glace"  printing,  471 

press  for,  472 
Glass-cleaning,  287 

albumenizing,  288 

collodionizing,  290 
Glasses,  measuring,  277 


Glass-house,  Canadian,  82 

construction,  75 

cooling  the,  103 

curiosity,  the,  91 

high  or  low  ?  83 

H.  Rocher's,  95 

J.  Landy,  80 

leaky,  94 

light  for  the,  76 

locality  for  the,  76 

of  Charles  Reutlinger,  85 

of  F.  Luckhardt,  89 

of  J.  H.  Kent,  79 

of  Loescher  and  Petsch,  84 

of  P.  A.  Mottu,  86 

of  P.  H.Rose,  103 

on  the  roof,  89 

N.  P.  A.,  96 

roof  construction,  93 

screens  outside,  101 

Texas,  a,  92 

typical  American,  77 
modified,  78 

with  north  front,  86 

with  ridge  roof,  81 

with  southern  exposure,  87,  88 
Gradation  of  light,  166 

of  tone  in  negatives,  293 
Grain,  process  of  photo-engraving,  513 
Granular  spots  in  negatives,  403 
Gravities,  specific,  278 
Green's  drying  stand,  279 
Green  fog  in  negatives,  389 
Grinding  of  lenses,  the,  35 
Grouping,  natural,  202 
Guide,  take  nature  as  our,  149 
Guillotine-stop,  the,  66 


HALF-TONE  process  for  photo-engrav- 
ing, 514 

Halo  about  the  high  lights,  401 
Handkerchiefs,  printing  frame  for,  466 
Handling  the  developer,  343 
Hand  screen,  the,  106 
Heat,  influence  of,  on  chemicals,  242 
Height,  in  landscape  work,  197 
Hepworth's  four-poster,  271.     . 
Hermagis'  sensitometer,  238 
Highest  art  is  felt,  the,  153 
High  lights,  halo  about  the,  401 
Hints  on  artistic  portraiture,  161 
on  the  use  of  backgrounds,  125 

of  stops,  70 
History  of  photography,  the,  17 


522 


INDEX. 


Holder,  negative,  for  development,  267 

for  developing  solution,  267 
Hood  for  lenses,  Thomas',  138 
Horizontal  tray  for  the  bath,  306 
Hydrochloric  acid  in  the  emulsion,  368 
Hydrometer,  actino,  the,  280 
Hydroquinone  developer,  358 
Hyposulphite  in  the  developer,  410 
test  for,  in  prints,  460 


TDEALIST  in  art,  the,  147 
JL    Illuminated  stop,  the,  72 
Illumination  of  the  dark-room,  410 

of  views,  202 
Image,    formation    of    the    photographic, 

22 

metallic,  building  up  the,  23 
Inclined  stop,  the,  70 
"Indispensable,"  the,  219 
Individuality  in  art,  151 
Influence  of  the  background,  124 

of  the  lens  on  the  exposure,  230 
Inspiration,  exposure  a  matter  of,  225 
Instantaneous  plates,  carbonate  of  soda ! 

developer  for,  379 
Instantaneous  views,  lenses  for,  211 
Intensification  of  American  films,  428 
Intensifier  for  dry  plates,  381 
Eder's,  402 
sublimate,  382 

Intention  and  meaning  of  the  artist,  158 
Iodide,  excess  of,  in  the  bath,  303 
removing  of,  in  the  bath,  304 
Iodine,  22 

Iodide  of  silver,  21,  22 
Iron,  printing  with  gallate  of,  494 

tannate  of,  494 
Isochromatic  photography,  504 

formulae,  507 
Ives's  orthochromatic  process,  505,  507 

process  of  photo-engraving,  514 
Isochromatic      photography,    Schumann's 

process,  508 
Mailman  &  Scolik's,  508 

TAVELLE  water,  preparation  of,  368 
eJ      Jean  Baptiste  Porta,  18,  19 
discovery  of,  18 


K 


ENTS  hand  screen,  106 
Kilburn's  plan  for  saving  the  negative, 

448 


Kilburn's  plan  of  pouring  silver  solutions, 

284 

Kimball's  model  printing-rooms,  442 
Klary's  system  of  lighting,  118 
Knowing  and  seeing  in  art,  156 
Kruse's  negative  numberer,  285 
Kurtz's  filter,  265 


T  ABORATORY,  Vidal's  portable,  28<> 
J_J    Lamp  for  heating  the  burnisher,  260 
Lamp,  Platt's  toning  bath,  454 
Landscape  photography,  192 

choice  of  lenses  for,  199 

work  lenses  for  instantaneous,  214 
Lantern  for  the  dark-room,  255 
Latchmore's  method  of  emptying   dishes, 

274 

Latitude  in  exposure,  227 
Law  governing  size  of  landscapes,  195 
Lens  hood,  Thomas',  138 

influence  of  the,  on  the  exposure,  230 
Lenses,  aberration  of,  45,  61 

about,  33 

angle  of  the,  33 

angle  of  view  of,  44 

astigmation,  61 

centring  the,  62 

chemical  focus  of,  63 

conjugated  foci  of,  42 

correction  of,  46 

curvature  of,  39 

defects  of,  49 

differences  in,  33 

distortion  of,  corrected,  59 

edging  the,  38 

equivalent  forms  of,  41 

for  landscape  work,  choice  of,  199 

focal  length  of,  196 

grinding  of,  35 

manufacture  of,  34 

mounting,  40 

optical  centre  of,  38 

over-corrected,  64 

perspective  angle  of,  194 

properties  of,  37 

to  find  the  foci  of,  41 

under-corrected,  64 

wide-angled,  48 
Light,  action  of,  30 

of  diffused,  223 

and  shade,  163 

chemical  action  of,  22,  27,  34 

dispersion  of,  29 

effect  produced  by,  30 


INDEX. 


528 


Light,  elements  of,  the,  27 

for  the  dark-room,  255,  256 

for  the  glass-house,  76 

for  the  studio,  118 

gradation  of  the,  166 

propagation  of,  34 

reducing  power  of,  23 

reflection  of,  28 

refraction  of,  28,  35 

screening  and  managing  the,  164 

seeing  things  in  their  best,  145 

sources  of,  27 

the  chief  producing  agent,  27 
Lighting  a  picture,  144 

Klary's  system  of,  118 

white  drapery,  117 
Literal,  photography  too,  172 
Litmus  paper,  276 
Locality  of  the  glass-house,  76 
Long's  method  of  securing  uniform  tem- 
perature, 260 

Lubricants  for  stoppers,  244 
Luminous  rays,  march  of  the,  65 


MANIPULATOR'S  day,  beginning    of 
the,  249 

Manufacture  of  emulsion,  315 
March  of  the  luminous  rays,  65 
Meaning  and  intention  of  the  artist,  158 
Measurer  View,  217 
Measuring  glasses,  277 
Medallion  camera,  137 
"Meisenbach"  process  of  photo-engraving, 

514 

Model  of  a  dark-room,  252 
Monckhoven's  developer,  356 
Mounting  and  finishing  the  print,  472 

boards,  test  for,  461 

brush,  473 

lenses,  40 

Moonlight  photographs.  412 
Multiplying  out-door  views,  209 


NATURAL  grouping,  202 
Nature,  study  of,  155 
as  our  guide,  149 
Negative,  artificial,  to  produce  by  etching, 

440 

Balagny's,  430 

becomes  dark  after  fixing,  402 
coarse-grained,  401 
diamond  the,  440 
film,  Thiobault's  support  for,  429 


Negative  glass,  preparation  of,  287 

holder  during  development,  267 

image,  flatness  of  the,  403 
too  great  density  of,  403 

intensifies,  Eder's,  402 

making,  ''dry,"  311 
"wet,"  287 
"paper "and  "film,"  418 

managing  an  overdeveloped,  384 

nuniberer,  Kruse's,  284 

retouching,  437,  438 

reversed  during  development,  401 

silver  solution  for,  291 

slow  fixing,  402 

retouching  and  doctoring  the,  435 

to  reduce  a,  384 

to  remove  varnish  from,  441 

too  thin,  373 

want  of  density  in,  404 

with  halo,  401 
Negatives,  annoyances  in,  302 

brilliant,  to  obtain,  292 

developing  the,  295 

fixation  of  the  "wet,"  298 

gradation  of  tone  in,  293 

intensification  of,  310 
Negatives,  overdeveloped,  362 

overexposed,  293 

stains  upon,  305 

underexposed,  293 

varnishing  the,  300 

washing  the,  299 

two  at  once,  253 

"New  method"  developer,  a,  351 
Newton's  developer,  354 
Nicol's  sensitometer,  237 
Niepce,  20 

Nitrate  bath,  treatment  of  a  disordered,  308 
for  negatives,  291 
purification  of  the,  307 

of  silver,  22 
Numberer,  Kruse's  negative,  284 


fABERNETTER'S  emulsion  method,  372 
\J     Obliterating  opaque  defects,  436 
Oil,  protecting  pyro  developer  with,  266 
Opal  glass  printing  processes,  497,  498 

printing  frame,  499 
Opaque  defects,  obliterating,  436 

spots,  403 

Opening  of  the  stop,  66 
Operations,  outdoor,  182 
Optical  centre  of  a  lens,  38,  53 
Originate,  178 


524 


INDEX. 


Orthochromatic  photography,  504 

formulae,  507 

Tves's  process,  505,  507 

Mailman  &  Scolik's  formulae,  508 

Schuman's  formulae,  508 

Vogel's  process,  506 
Outdoor  operations,  182 
studio,  102 
views,  atmosphere,  185 

climb  for,  187 

clouds  in,  190 

combining  negatives  of,  210 

composition,  185 

correct  perspective,  211 

difficulties  and  drawbacks  in,  208 

distance  and  elevation,  195 

examples,  188 

foregrounds,  184 

height  of,  197 

law  governing  size,  195 

multiplying,  209 

overtoiled,  225 

perspective  in,  193 

size  of,  198 

skies  in,  190 

studying  the  foreground,  205 

the  right  lens  for,  194,  196 

times  of  day,  190 

water  in,  185 

Outside  screens  for  the  studio,  101 
Overdeveloped  negatives,  362 

plate,  managing  an,  384 
Overexposure,  developer  for,  345 
Overtiming,  225 

a  plea  for,  359 

Oxalate  developer  for  American  films,  427 
ferrous,  developer,  357 


PAPEK,  apparatus  for  silvering,  449 
for  drying,  450 

coated  with  gelatine  emulsion,  411 
cutting  the,  446 
making  limp,  the  dish  for,  447 
negatives,  418 
curling,  420 
illustrated,  420 
oxalate  developer  for,  420 
printing  the,  421 
treatment  of,  422 
Kilburn's  plan  of  preparing,  448 
Paraffine,  the  use  of,  258 
Parallactic  erroi,  the,  62 
Particulars,  printing  room,  463 
Peculiar  printing  processes,  474 


Perspective,  192 

angle  of  lenses,  194 

correct,  211 
Photo-engraving,  509 

alloy  for,  514 

bleaching  for,  510 

"etching"  process,  512 

"grain"  process,  513 

half-tone  process,  514 

illustrated,  510 

Ives'  process,  514 

"Meisenbach"  process,  514 

"swelling"  process,  511 
Photographic  car  model,  98 

image,  formation  of  the,  22 

tent  model,  100 
Photographing  animals,  200 

on  wood,  515 

Photographs,  moonlight,  412 
Photography,  17,  20 

discovery  of,  17 

future  of,  17 

history  of,  17 

outdoor,  182 

the  new  baby  born,  179 

theory  of,  21 
Lea's,  24 

too  literal,  172 

various  views  of,  21 
Picture,  conception  of  a,  203 

lighting  and  overlighting,  144 

treatment  of  a,  143 
Piles's  silver  tester,  282 
Pinhole  camera,  the,  61 
Pinholes  in  negatives,  293 
Pipette,  the,  270 
Plain  paper,  printing  on,  475 
Plaited  filter,  to  make  a,  263 
Plate,  preparation  of  the,  376 

-rocker  during  development,  268,  269 

-tongs  for  use  during  development,  269 
Platinotype  process,  Willis's,  488,  489,  490 
Platt's  filter,  265 
Plea  for  overtiming,  a,  359 
Porcelain  glass,  carbon  printing  on,  501 
chloride  printing  on,  498 
emulsion  printing  on,  498 
printing  on,  497 
Portable  laboratory,  Vidal's  286 
Porta,  Jean  Baptiste,  18,  19 
Portrait  photography,  charges  against,  148 
Portraiture  by  artificial  light,  412 
Position  of  the  camera,  best,  119 
Positives  in  the  camera  direct,  412 
Poster,  Hepworth's  four,  271 


INDEX. 


525 


Potash  solution,  the,  352 
Pouring  solutions,  Kilburn's  plan  of,  284 
Powell's  printing  process,  493 
Pressure,  modification  by,  241 
Principles,  application  of  art,  141 
Printer,  the,  should  be  educated,  469 
Printing  au  deux  crayons,  469 

bath,  463 

Berlin  pictures,  470 

blisters  in,  459 

blue,  491 

carbon,  501 

drawbacks  and  defects  in,  458 

enlargements  on  bromo-gelatine  paper, 

483 

apparatus  for,  Beach's,  485,   486, 
487 

film  negatives,  433 

frame  for  aquatints,  465 
for  handkerchiefs,  466 

from  flat  negatives,  469 

from  hard  negatives,  469 

Glace  pictures,  471 

press  for,  472 

keeping  tally  of  the,  469 

on  albumen  paper,  442 

on  Anthony's  gelatine  paper,  479 

on  aristotype,  paper,  476 

on  bromo-gelatine  paper,  478 

on  gelatino-chloride  paper,  478 

on  plain  paper,  475 

on  platinotype  paper,  488 

on  porcelain  glass,  497 

on  ready  sensitized  paper,  474 

on  watch  dials,  500 

paper  negatives,  421 

processes,  peculiar,  474 

room  particulars,  463 

rooms,  KimbalPs  model,  442 

skies,  468 

theory  of  silver,  445 

Waymouth's  vignette  papers,  467 

Willis's  process  for  aniline,  493 

with  gallate  of  iron,  494 

with  gelatino-bromide,  413 

with  gelatino-chloride,  413 

with  tannate  of  iron,  494 
Prints  are  red  after  fuming,  450 

drying  the,  462 

fixing  the,  455 

fuming  the,  464 

mounting  and  finishing  the,  472 
brush  for,  473 

varied  tones  of  albumen,  452 

washing  the,  456,  460 


Prints,  washing,  apparatus  for,  457 
Prism,  the,  36     • 

for  reversing  ferrotypes,  139 
Prize  emulsion,  the  Wilson-Paget,  368 
Producing  agent,  light  the  chief,  27 
Properties  of  lenses,  37 
Protecting  pyro  developer  with  oil,  266 
Pure  chemicals  best,  242 

water,  to  obtain,  246,  262 
Purity  of  chemicals,  test  for,  247 
Pyro  alkaline  developer  in  one  solution, 

347 
in  three  solutions,  348 

and  carbonate  of  potash  developer,  344 

developer,  protecting,  with  oil,  266 

in  solution,  to  keep,  349 

solution,  the,  352 


Q 


UICK  developer,  a,  351 
plates,  227 


RATIONALE  of  the  developer,  355 
Rawson's  multiplier,  140 
Ready  sensitized  paper,  printing  on,  474 
Realist  in  art,  the,  147 
Recovery  of  silver  from  waste  emulsion,  414 
Red  fog,  389 

Reduce  a  negative,  to,  384 
Reducing  agents,  385 

density,  386 
Reflection  of  light,  28 
Reflector,  concave,  Gris wold's,  113 

Coddington's,  117 

Kurtz's  counter,  114 
Reflectors  and  side  screens,  111 
Refraction  of  light,  28 
Regulator,  Foucault's  time,  232 
Relief  after  fixing,  416 
Removing  the  varnish,  302 

varnish,  414 
Rest,  the  eye-,  127 
Retouching,  414 

and  doctoring  the  negative,  435 

chemical,  436 

colored  collodion  for,  435 
Reversing    the   negative    during  develop- 
ment, 401 

prism,  139 

Revolving  background,  the,  123 
Ridge-roof  studio,  81 
Roche,  Triphaine  de  la,  19 
Rocker  for  plates  during  development,  268, 
269 


526 


INDEX. 


Roll-holder,  Eastman's,  425,  426 
Roof,  construction  of  the  studio,  93 

studio  on  the,  89 
Root's  contrivance  for  cleaning  glass,  288 

cooling  contrivance,  259 
Rule  for  exposure,  no,  225 
Rules  in  art,  fundamental,  161 


SALTS  of  mercury,  failures  with,  406 
Scheele,  19 

Scotford's  cooling  contrivance,  261 
Screen  and  point  of  sight,  110 

studio,  Densmore's,  107 
Hall's,  109 
Kibbe's,  109 
Manville's,  109 
Mason's,  110 

the  hand,  106 

Screening  and  managing  the  light,  164,  165 
Sculptor's  ideas  of  photography,  a,  160 
Scum,  306 

Selection  of  view,  206 
Selective  ability,  147 
Sensitiveness  of  bromide  of  silver,  417 

of  dry  plates,  relative,  314 

the  result  of  keeping,  416 
Sensitizing  bath  for  "wet"  plates,  291 
Sensitometer,  Hermagis',  238 

Nicol's,  237 

VogePs,  236 

Warnerke's,  234 

Sentiment  or  conception,  artistic,  159 
Seeing  and  knowing  in  art,  156 
Seeing  things  in  their  best  light,  145 
Shadow  experiment,  Prof.  Charles',  19 
Shutter,  Coddington's  baby,  137 

speed  of  the  exposing,  231 

Thomas'  lens,  138 
Shutters,  exposing,  211 
Side-light,  high,  working  a,  82 
Side  screens  and  reflectors,  111 

screen,  Cramer's,  112 
Coddington's,  117 
Sight,  artistic,  142 
Silver,  bromide  of,  22 

chloride  of,  21 

iodide  of,  21 

nitrate  of,  22 

printing,  the  theory  of,  445 

saver,  Webster's,  283 
Benecke's,  283 

solution,  pouring  the,  284 
for  negatives,  291 

subiodide  of,  22 


Silver  tester,  Pile's,  282 

Vogel's,  281 
Simplicity,  145 
Sink  for  the  dark-room,  251 
Siphon,  the,  272 

Chandler's,  273 

Gause's,  272 

Stebbing's,  275 
Size  determined  by  the  angle  of  the  lens,  33 

of  landscapes,  law  governing,  195,  198 
Skies  in  outdoor  views,  190 

printing  in,  468 
Sky  diaphragm,  Fowler's,  192 
Skylight,  under  the,  105 
Slow  developing  occurs,  398 

emulsion  for  landscape  work,  318 

fixing  of  the  negative,  402 

go,  in  developing,  342 
Soda  developer,  carbonate  of,  341) 
Solution,  nitrate  of  silver  of,  22 
Solutions,  testing  the  strength  of,  280 

vary  the,  with  the  temperature,  243 
Soul,  expression  of,  in  art,  438 
Specific  gravities,  278 
Spencer's  copying  camera,  129 

curtain  stand,  133 
Spots,  and  rings  appear,  398 

dull,  404 

engravings  of,  various,  405 

in  negatives,  clear,  394 

opaque,  400,  403 

round  and  matt,  404 

semi-transparent,  404 
Stains,  to  remove  from,  negatives,  393 

upon  negatives,  305 

yellow,  in  negatives,  392 
Stand  for  drying  negatives,  279 
Stebbing's  dropping-bottle,  271 
Stebbing's  siphon,  275 

method  of  emptying  dishes,  275 
Steinheil's  new  lens,  65 
Still,  Smith's  water,  262 
Stirring  apparatus   for  emulsion,  Vogel's, 

323 

Stock  solution  for  developer,  "dry,"  352 
Stop,  illuminated,  72 

opening  of  the,  67 

the  diaphragm  or,  65 

the  guillotine,  66 

the  flare,  69 

Zentmayer's  adjustable,  73 
Stops,  hints  on  the  use  of,  70 

inclined,  the,  71 
Stoppers,  lubricants  for,  244 
Story,  telling  the,  205 


INDEX. 


527 


Stirator,  Londe's,  for  holding  films,  433 
Strength  of  solutions,  280 

of  the  fixing  bath,  416 
Studies  of  foreground,  205 
Studio,  cooling  the,  103 

curiosity,  the,  91 

curtains  for  the,  105 

light  for  the,  118 

on  the  roof,  87 

outdoor,  102 

outside  screens,  101 

position  of  the  camera,  119 

roof  construction,  93 

with  a  north  front,  86 

with  ridge  roof,  81 

with  southern  exposure,  87,  88 
Subiodide  of  silver,  22 
Substrata  for  gelatine  plates,  416 
Sub-studio,  Foss's,  115 
Sulphite  of  ammonia  developer,  357 
Sunlight  is  best,  228 
Surfaces  for  focussing,  134 
"Swelling"  process  of  photo-engraving,  511 


mABLE,  Hall's  copying,  130 

_L     Talbot,  Fox,  20 

Tally,  keeping,  of  prints,  469 

Tameness,  145 

Tanks  for  the  dark-room,  258 

Tartrate  of  iron,   Poitevin's  process  with, 

240 
Taste,  elevation  of,  153 

variation  of,  146 

Tear  drops  on  emulsion  negatives,  395 
Technique,  169 

means  workmanship,  170 
Telling  the  Story,  205 
Temperature,  emulsion  made  at  low,  333 
made  at  high,  334 

even,  Long's  method  of  securing,  260 

uniform,  257 

vary  the  solutions  with  the,  243 

watch  the,  242 

Tent,  model  photographic,  100 
Tents  for  landscape  work,  215 
Test  for  focus,  Chute's,  132 
Tester,  Pile's  silver,  282 

Vogel's  silver,  281 

Testing  the  strength  of  solutions,  280 
Tests  for  purity  of  chemicals,  247 

water,  248 
Theory  of  development,  240 

of  photography,  the,  21 
Lea's,  24 


Thiebault's  support  for  films,  429 
Thin  and  ghostly  images,  383 

too,  the  negative,  373 
Things  to  don't,  406 
Time  of  day,  the,  221 

regulator,  Foucault's,  233 

the  question  of,  220 
Tongs,  plate,  for  development,  269 
Toning  albumen  prints,  450 

bath,  451 

lamp,  454 

varied,  of  prints,  451 
Top-side  light  glass-house,  best,  79 
Towler's  sky  diaphragm,  192 
Too  thin  the  negative,  373 
Transparencies  with  gelatine  plates,  411 
Tray  for  fixing  emulsion  plates,  366 

for  washing  emulsion  plates,  373 

horizontal,  for  the  bath,  306 

Vidal's  filtering,  284 
Treatment  of  a  disordered  bath,  308 

of  a  picture,  143 

variety  of,  wanted,  151 


UNDER  exposure,  developer  for,  345 
the  skylight,  105 
Uniform  temperature,  value  of,  259 

Long's  method  of,  260 
Universally  useful  developer,  351 
Unknown  exposure,  to  treat,  360 


TTARIATION  of  tastes,  146 
V      Variety  of  treatment  wanted,  151 
Varnish  pourers,  301,  302 

removing  films  of,  414 
the,  302 

to  remove  from  negatives,  441 
Varnishing,  fading  of  the,  4)2 

the  negative,  300 
Veiling  of  the  film,  388 
Ventilator,  a  dark-room,  254 
Vidal's  filtering  tray,  284 

portable  laboratory,  286 
View  measurer,  217 

photography,  192 

selection  of,  206 
Vignettes,  printing,  467 
Vignetting  in  the  camera,  135 
Vision,  31 
Vogel's  sensitometer,  236 

silver  tester,  282 

stirring  apparatus  for  emulsion,  323 


528 


INDEX. 


WARNERKE'S  sensitoineter,  234 
Washing  apparatus,  457 
Bettini's,  300 
for  "dry"  negatives,  364 
Washing  emulsion  plates,  335 

apparatus  for,  335,  336,  376 
the  negative,  "  wet,"  299 
the  prints,  456 
thorough,  460 

tray  for  "dry"  negatives,  367 
two  negatives  at  once,  253 
Waste-pipe,  plan  of,  261 
Watch  dials,  printing  on,  500 

the  temperature,  243 
Water,  distillation  of,  262 
distilled,  263 
filtration  of,  263 
-hammer,  the,  247 

tests,  248 

javelle,  preparation  of,  368 
to  obtain  pure,  246,  262 
Watt,  James,  19 
Waymouth's  vignette  papers,  printing  with, 

467 
Webster's  method  of  emptying  dishes,  274 


Wedgewood,  19 
Weighing,  exactitude  in,  277 
Wells'  plan  for  waste-pipe,  261 
"Wet"  negative  making,  287 
When  to  expose,  226 
Where  does  art  come  in  ?  178 
White  powder  on  emulsion  plates,  396 
Wide-angled  lenses,  48 
Wilson-Paget  prize  emulsion,  368 
Willis'  aniline  process,  493 
Workmanship,  technique  means,  170 
Wood,  photography  on,  515 
Woodman's  filter,  264 


T^ELLOW  stains  on  negatives,  392,  403 


r/ENTMAYER'S   adjustable  diaphragm. 
/J     73 

Zig-zag  lines  on  the  plate,  400 
Zinc-etching,  509-512 
illustrated,  510 


a 


YC   13797 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 


*  *  r* 


